quantum-espresso/CPV/Doc/INPUT_CP.def

2395 lines
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Modula-2

input_description -distribution {Quantum Espresso} -package CP -program cp.x {
toc {}
intro {
Input data format: { } = optional, [ ] = it depends, | = or
All quantities whose dimensions are not explicitly specified are in
HARTREE ATOMIC UNITS. Charge is "number" charge (i.e. not multiplied
by e); potentials are in energy units (i.e. they are multiplied by e)
BEWARE: TABS, DOS <CR><LF> CHARACTERS ARE POTENTIAL SOURCES OF TROUBLE
Comment lines in namelists can be introduced by a "!", exactly as in
fortran code. Comments lines in ``cards'' can be introduced by
either a "!" or a "#" character in the first position of a line.
Do not start any line in ``cards'' with a "/" character.
Structure of the input data:
===============================================================================
&CONTROL
...
/
&SYSTEM
...
/
&ELECTRONS
...
/
[ &IONS
...
/ ]
[ &CELL
...
/ ]
[ &WANNIER
...
/ ]
ATOMIC_SPECIES
X Mass_X PseudoPot_X
Y Mass_Y PseudoPot_Y
Z Mass_Z PseudoPot_Z
ATOMIC_POSITIONS { alat | bohr | crystal | angstrom }
X 0.0 0.0 0.0 {if_pos(1) if_pos(2) if_pos(3)}
Y 0.5 0.0 0.0
Z O.0 0.2 0.2
[ CELL_PARAMETERS { alat | bohr | angstrom }
v1(1) v1(2) v1(3)
v2(1) v2(2) v2(3)
v3(1) v3(2) v3(3) ]
[ OCCUPATIONS
f_inp1(1) f_inp1(2) f_inp1(3) ... f_inp1(10)
f_inp1(11) f_inp1(12) ... f_inp1(nbnd)
[ f_inp2(1) f_inp2(2) f_inp2(3) ... f_inp2(10)
f_inp2(11) f_inp2(12) ... f_inp2(nbnd) ] ]
[ CONSTRAINTS
nconstr { constr_tol }
constr_type(.) constr(1,.) constr(2,.) [ constr(3,.) constr(4,.) ] { constr_target(.) } ]
[ ATOMIC_FORCES
label_1 Fx(1) Fy(1) Fz(1)
.....
label_n Fx(n) Fy(n) Fz(n) ]
}
#
# namelist CONTROL
#
namelist CONTROL {
var calculation -type CHARACTER {
default { 'cp' }
info {
a string describing the task to be performed:
'cp',
'scf',
'nscf',
'relax',
'vc-relax',
'vc-cp',
'cp-wf',
'vc-cp-wf'
(vc = variable-cell).
(wf = Wannier functions).
}
}
var title -type CHARACTER {
default {'MD Simulation '}
info {
reprinted on output.
}
}
var verbosity -type CHARACTER {
default {'low'}
info {
In order of decreasing verbose output:
'debug' | 'high' | 'medium' | 'low','default' | 'minimal'
}
}
var isave -type INTEGER {
see { ndr }
see { ndw }
default { 100 }
info {
Number of steps between successive savings of
information needed to restart the run.
}
}
var restart_mode -type CHARACTER {
default { 'restart' }
info {
'from_scratch' : from scratch
'restart' : from previous interrupted run
'reset_counters' : continue a previous simulation,
performs "nstep" new steps, resetting
the counter and averages
}
}
var nstep -type INTEGER {
info {
number of Car-Parrinello steps performed in this run
}
default {
50
}
}
var iprint -type INTEGER {
default { 10 }
info {
Number of steps between successive writings of relevant physical quantities
to files named as "prefix.???" depending on "prefix" parameter.
In the standard output relevant quantities are written every 10*iprint steps.
}
}
var tstress -type LOGICAL {
default { .false. }
info {
Write stress tensor to standard output each "iprint" steps.
It is set to .TRUE. automatically if
calculation='vc-relax'
}
}
var tprnfor -type LOGICAL {
default {.false.}
info {
print forces. Set to .TRUE. when ions are moving.
}
}
var dt -type REAL {
default { 1.D0 }
info {
time step for molecular dynamics, in Hartree atomic units
(1 a.u.=2.4189 * 10^-17 s : beware, PW code use
Rydberg atomic units, twice that much!!!)
}
}
var outdir -type CHARACTER {
default {
value of the ESPRESSO_TMPDIR environment variable if set;
current directory ('./') otherwise
}
info {
input, temporary, trajectories and output files are found
in this directory.
}
}
var saverho -type LOGICAL {
info {
This flag controls the saving of charge density in CP codes:
If .TRUE. save charge density to restart dir,
If .FALSE. do not save charge density.
}
}
var prefix -type CHARACTER {
default { 'cp' }
info {
prepended to input/output filenames:
prefix.pos : atomic positions
prefix.vel : atomic velocities
prefix.for : atomic forces
prefix.cel : cell parameters
prefix.str : stress tensors
prefix.evp : energies
prefix.hrs : Hirshfeld effective volumes (ts-vdw)
prefix.eig : eigen values
prefix.nos : Nose-Hoover variables
prefix.spr : spread of Wannier orbitals
prefix.wfc : center of Wannier orbitals
prefix.ncg : number of Poisson CG steps (PBE0)
}
}
var ndr -type INTEGER {
default { 50 }
info {
Units for input and output restart file.
}
}
var ndw -type INTEGER {
default { 50 }
info {
Units for input and output restart file.
}
}
var tabps -type LOGICAL {
default {.false.}
info {
.true. to compute the volume and/or the surface of an isolated
system for finite pressure/finite surface tension calculations
(PRL 94, 145501 (2005); JCP 124, 074103 (2006)).
}
}
var max_seconds -type REAL {
default { 1.D+7, or 150 days, i.e. no time limit }
info {
jobs stops after max_seconds CPU time. Used to prevent
a hard kill from the queuing system.
}
}
var etot_conv_thr -type REAL {
default { 1.0D-4 }
info {
convergence threshold on total energy (a.u) for ionic
minimization: the convergence criterion is satisfied
when the total energy changes less than etot_conv_thr
between two consecutive scf steps.
See also forc_conv_thr - both criteria must be satisfied
}
}
var forc_conv_thr -type REAL {
default { 1.0D-3 }
info {
convergence threshold on forces (a.u) for ionic
minimization: the convergence criterion is satisfied
when all components of all forces are smaller than
forc_conv_thr.
See also etot_conv_thr - both criteria must be satisfied
}
}
var ekin_conv_thr -type REAL {
default { 1.0D-6 }
info {
convergence criterion for electron minimization:
convergence is achieved when "ekin < ekin_conv_thr".
See also etot_conv_thr - both criteria must be satisfied.
}
}
var disk_io -type CHARACTER {
default { 'default' }
info {
'high': CP code will write Kohn-Sham wfc files and additional
information in data-file.xml in order to restart
with a PW calculation or to use postprocessing tools.
If disk_io is not set to 'high', the data file
written by CP will not be readable by PW or PostProc.
}
}
var memory -type CHARACTER {
default { 'default' }
info {
'small': NO LONGER IMPLEMENTED SINCE v.6.3
memory-saving tricks are implemented. Currently:
- the G-vectors are sorted only locally, not globally
- they are not collected and written to file
For large systems, the memory and time gain is sizable
but the resulting data files are not portable - use it
only if you do not need to re-read the data file
}
}
var pseudo_dir -type CHARACTER {
default {
value of the $ESPRESSO_PSEUDO environment variable if set;
'$HOME/espresso/pseudo/' otherwise
}
info {
directory containing pseudopotential files
}
}
var tefield -type LOGICAL {
default { .FALSE. }
info {
If .TRUE. a homogeneous finite electric field described
through the modern theory of the polarization is applied.
}
}
}
#
# NAMELIST &SYSTEM
#
namelist SYSTEM {
var ibrav -type INTEGER {
status { REQUIRED }
info {
Bravais-lattice index. If ibrav /= 0, specify EITHER
[ celldm(1)-celldm(6) ] OR [ A,B,C,cosAB,cosAC,cosBC ]
but NOT both. The lattice parameter "alat" is set to
alat = celldm(1) (in a.u.) or alat = A (in Angstrom);
see below for the other parameters.
For ibrav=0 specify the lattice vectors in CELL_PARAMETER,
optionally the lattice parameter alat = celldm(1) (in a.u.)
or = A (in Angstrom), or else it is taken from CELL_PARAMETERS
ibrav structure celldm(2)-celldm(6)
or: b,c,cosbc,cosac,cosab
0 free
crystal axis provided in input: see card CELL_PARAMETERS
1 cubic P (sc)
v1 = a(1,0,0), v2 = a(0,1,0), v3 = a(0,0,1)
2 cubic F (fcc)
v1 = (a/2)(-1,0,1), v2 = (a/2)(0,1,1), v3 = (a/2)(-1,1,0)
3 cubic I (bcc)
v1 = (a/2)(1,1,1), v2 = (a/2)(-1,1,1), v3 = (a/2)(-1,-1,1)
-3 cubic I (bcc), more symmetric axis:
v1 = (a/2)(-1,1,1), v2 = (a/2)(1,-1,1), v3 = (a/2)(1,1,-1)
4 Hexagonal and Trigonal P celldm(3)=c/a
v1 = a(1,0,0), v2 = a(-1/2,sqrt(3)/2,0), v3 = a(0,0,c/a)
5 Trigonal R, 3fold axis c celldm(4)=cos(gamma)
The crystallographic vectors form a three-fold star around
the z-axis, the primitive cell is a simple rhombohedron:
v1 = a(tx,-ty,tz), v2 = a(0,2ty,tz), v3 = a(-tx,-ty,tz)
where c=cos(gamma) is the cosine of the angle gamma between
any pair of crystallographic vectors, tx, ty, tz are:
tx=sqrt((1-c)/2), ty=sqrt((1-c)/6), tz=sqrt((1+2c)/3)
-5 Trigonal R, 3fold axis <111> celldm(4)=cos(gamma)
The crystallographic vectors form a three-fold star around
<111>. Defining a' = a/sqrt(3) :
v1 = a' (u,v,v), v2 = a' (v,u,v), v3 = a' (v,v,u)
where u and v are defined as
u = tz - 2*sqrt(2)*ty, v = tz + sqrt(2)*ty
and tx, ty, tz as for case ibrav=5
Note: if you prefer x,y,z as axis in the cubic limit,
set u = tz + 2*sqrt(2)*ty, v = tz - sqrt(2)*ty
See also the note in Modules/latgen.f90
6 Tetragonal P (st) celldm(3)=c/a
v1 = a(1,0,0), v2 = a(0,1,0), v3 = a(0,0,c/a)
7 Tetragonal I (bct) celldm(3)=c/a
v1=(a/2)(1,-1,c/a), v2=(a/2)(1,1,c/a), v3=(a/2)(-1,-1,c/a)
8 Orthorhombic P celldm(2)=b/a
celldm(3)=c/a
v1 = (a,0,0), v2 = (0,b,0), v3 = (0,0,c)
9 Orthorhombic base-centered(bco) celldm(2)=b/a
celldm(3)=c/a
v1 = (a/2, b/2,0), v2 = (-a/2,b/2,0), v3 = (0,0,c)
-9 as 9, alternate description
v1 = (a/2,-b/2,0), v2 = (a/2, b/2,0), v3 = (0,0,c)
10 Orthorhombic face-centered celldm(2)=b/a
celldm(3)=c/a
v1 = (a/2,0,c/2), v2 = (a/2,b/2,0), v3 = (0,b/2,c/2)
11 Orthorhombic body-centered celldm(2)=b/a
celldm(3)=c/a
v1=(a/2,b/2,c/2), v2=(-a/2,b/2,c/2), v3=(-a/2,-b/2,c/2)
12 Monoclinic P, unique axis c celldm(2)=b/a
celldm(3)=c/a,
celldm(4)=cos(ab)
v1=(a,0,0), v2=(b*cos(gamma),b*sin(gamma),0), v3 = (0,0,c)
where gamma is the angle between axis a and b.
-12 Monoclinic P, unique axis b celldm(2)=b/a
celldm(3)=c/a,
celldm(5)=cos(ac)
v1 = (a,0,0), v2 = (0,b,0), v3 = (c*cos(beta),0,c*sin(beta))
where beta is the angle between axis a and c
13 Monoclinic base-centered celldm(2)=b/a
celldm(3)=c/a,
celldm(4)=cos(gamma)
v1 = ( a/2, 0, -c/2),
v2 = (b*cos(gamma), b*sin(gamma), 0 ),
v3 = ( a/2, 0, c/2),
where gamma=angle between axis a and b projected on xy plane
-13 Monoclinic base-centered celldm(2)=b/a
(unique axis b) celldm(3)=c/a,
celldm(5)=cos(beta)
v1 = ( a/2, b/2, 0),
v2 = ( -a/2, b/2, 0),
v3 = (c*cos(beta), 0, c*sin(beta)),
where beta=angle between axis a and c projected on xz plane
IMPORTANT NOTICE: until QE v.6.4.1, axis for ibrav=-13 had a
different definition: v1(old) = v2(now), v2(old) = -v1(now)
14 Triclinic celldm(2)= b/a,
celldm(3)= c/a,
celldm(4)= cos(bc),
celldm(5)= cos(ac),
celldm(6)= cos(ab)
v1 = (a, 0, 0),
v2 = (b*cos(gamma), b*sin(gamma), 0)
v3 = (c*cos(beta), c*(cos(alpha)-cos(beta)cos(gamma))/sin(gamma),
c*sqrt( 1 + 2*cos(alpha)cos(beta)cos(gamma)
- cos(alpha)^2-cos(beta)^2-cos(gamma)^2 )/sin(gamma) )
where alpha is the angle between axis b and c
beta is the angle between axis a and c
gamma is the angle between axis a and b
}
}
group {
label { Either: }
dimension celldm -start 1 -end 6 -type REAL {
see { ibrav }
info {
Crystallographic constants - see the "ibrav" variable.
Specify either these OR A,B,C,cosAB,cosBC,cosAC NOT both.
Only needed values (depending on "ibrav") must be specified
alat = celldm(1) is the lattice parameter "a" (in BOHR)
If ibrav=0, only celldm(1) is used if present;
cell vectors are read from card CELL_PARAMETERS
}
}
label { Or: }
vargroup -type REAL {
var A
var B
var C
var cosAB
var cosAC
var cosBC
info {
Traditional crystallographic constants: a,b,c in ANGSTROM
cosAB = cosine of the angle between axis a and b (gamma)
cosAC = cosine of the angle between axis a and c (beta)
cosBC = cosine of the angle between axis b and c (alpha)
The axis are chosen according to the value of "ibrav".
Specify either these OR "celldm" but NOT both.
Only needed values (depending on "ibrav") must be specified
The lattice parameter alat = A (in ANGSTROM )
If ibrav = 0, only A is used if present;
cell vectors are read from card CELL_PARAMETERS
}
}
}
var nat -type INTEGER {
status { REQUIRED }
info {
number of atoms in the unit cell
}
}
var ntyp -type INTEGER {
status { REQUIRED }
info {
number of types of atoms in the unit cell
}
}
var nbnd -type INTEGER {
default {
for an insulator, nbnd = number of valence bands
(nbnd = # of electrons /2);
for a metal, 20% more (minimum 4 more)
}
info {
number of electronic states (bands) to be calculated.
Note that in spin-polarized calculations the number of
k-point, not the number of bands per k-point, is doubled
}
}
var tot_charge -type REAL {
default { 0.0 }
info {
total charge of the system. Useful for simulations with charged cells.
By default the unit cell is assumed to be neutral (tot_charge=0).
tot_charge=+1 means one electron missing from the system,
tot_charge=-1 means one additional electron, and so on.
In a periodic calculation a compensating jellium background is
inserted to remove divergences if the cell is not neutral.
}
}
var tot_magnetization -type REAL {
default { -1 [unspecified] }
info {
total majority spin charge - minority spin charge.
Used to impose a specific total electronic magnetization.
If unspecified, the tot_magnetization variable is ignored
and the electronic magnetization is determined by the
occupation numbers (see card OCCUPATIONS) read from input.
}
}
var ecutwfc -type REAL {
status { REQUIRED }
info {
kinetic energy cutoff (Ry) for wavefunctions
}
}
var ecutrho -type REAL {
default { 4 * ecutwfc }
info {
kinetic energy cutoff (Ry) for charge density and potential
For norm-conserving pseudopotential you should stick to the
default value, you can reduce it by a little but it will
introduce noise especially on forces and stress.
If there are ultrasoft PP, a larger value than the default is
often desirable (ecutrho = 8 to 12 times ecutwfc, typically).
PAW datasets can often be used at 4*ecutwfc, but it depends
on the shape of augmentation charge: testing is mandatory.
The use of gradient-corrected functional, especially in cells
with vacuum, or for pseudopotential without non-linear core
correction, usually requires an higher values of ecutrho
to be accurately converged.
}
}
vargroup -type INTEGER {
see { ecutrho }
var nr1
var nr2
var nr3
info {
three-dimensional FFT mesh (hard grid) for charge
density (and scf potential). If not specified
the grid is calculated based on the cutoff for
charge density.
}
}
vargroup -type INTEGER {
var nr1s
var nr2s
var nr3s
info {
three-dimensional mesh for wavefunction FFT and for the smooth
part of charge density ( smooth grid ).
Coincides with nr1, nr2, nr3 if ecutrho = 4 * ecutwfc ( default )
}
}
vargroup -type INTEGER {
var nr1b
var nr2b
var nr3b
info {
dimensions of the "box" grid for Ultrasoft pseudopotentials
must be specified if Ultrasoft PP are present
}
}
var occupations -type CHARACTER {
info {
a string describing the occupation of the electronic states.
In the case of conjugate gradient style of minimization
of the electronic states, if occupations is set to 'ensemble',
this allows ensemble DFT calculations for metallic systems
}
}
var degauss -type REAL {
default { 0.D0 Ry }
info {
parameter for the smearing function, only used for ensemble DFT
calculations
}
}
var smearing -type CHARACTER {
info {
a string describing the kind of occupations for electronic states
in the case of ensemble DFT (occupations == 'ensemble' );
now only Fermi-Dirac ('fd') case is implemented
}
}
var nspin -type INTEGER {
default { 1 }
info {
nspin = 1 : non-polarized calculation (default)
nspin = 2 : spin-polarized calculation, LSDA
(magnetization along z axis)
}
}
var ecfixed -type REAL { default { 0.0 }; see { q2sigma } }
var qcutz -type REAL { default { 0.0 }; see { q2sigma } }
var q2sigma -type REAL {
default { 0.1 }
info {
ecfixed, qcutz, q2sigma: parameters for modified functional to be
used in variable-cell molecular dynamics (or in stress calculation).
"ecfixed" is the value (in Rydberg) of the constant-cutoff;
"qcutz" and "q2sigma" are the height and the width (in Rydberg)
of the energy step for reciprocal vectors whose square modulus
is greater than "ecfixed". In the kinetic energy, G^2 is
replaced by G^2 + qcutz * (1 + erf ( (G^2 - ecfixed)/q2sigma) )
See: M. Bernasconi et al, J. Phys. Chem. Solids 56, 501 (1995)
}
}
var input_dft -type CHARACTER {
default { read from pseudopotential files }
info {
Exchange-correlation functional: eg 'PBE', 'BLYP' etc
See Modules/funct.f90 for allowed values.
Overrides the value read from pseudopotential files.
Use with care and if you know what you are doing!
Use 'PBE0' to perform hybrid functional calculation using Wannier functions.
Allowed calculation: 'cp-wf' and 'vc-cp-wf'
See CP specific user manual for further guidance (or in CPV/Doc/user_guide.tex)
and examples in CPV/examples/EXX-wf-example.
Also see related keywords starting with exx_.
}
}
var exx_fraction -type REAL {
default { it depends on the specified functional }
info {
Fraction of EXX for hybrid functional calculations. In the case of
input_dft='PBE0', the default value is 0.25.
}
}
var lda_plus_u -type LOGICAL {
default { .FALSE. }
info { lda_plus_u = .TRUE. enables calculation with LDA+U
("rotationally invariant"). See also Hubbard_U.
Anisimov, Zaanen, and Andersen, PRB 44, 943 (1991);
Anisimov et al., PRB 48, 16929 (1993);
Liechtenstein, Anisimov, and Zaanen, PRB 52, R5467 (1994);
Cococcioni and de Gironcoli, PRB 71, 035105 (2005).
}
}
dimension Hubbard_U -start 1 -end ntyp -type REAL {
default { 0.D0 for all species }
status {
LDA+U works only for a few selected elements. Modify
CPV/ldaU.f90 if you plan to use LDA+U with an
element that is not configured there.
}
info {
Hubbard_U(i): parameter U (in eV) for LDA+U calculations.
Currently only the simpler, one-parameter LDA+U is
implemented (no "alpha" or "J" terms)
}
}
var vdw_corr -type CHARACTER {
default { 'none' }
info {
Type of Van der Waals correction. Allowed values:
'grimme-d2', 'Grimme-D2', 'DFT-D', 'dft-d': semiempirical Grimme's DFT-D2.
Optional variables: "london_s6", "london_rcut"
S. Grimme, J. Comp. Chem. 27, 1787 (2006),
V. Barone et al., J. Comp. Chem. 30, 934 (2009).
'TS', 'ts', 'ts-vdw', 'ts-vdW', 'tkatchenko-scheffler': Tkatchenko-Scheffler
dispersion corrections with first-principle derived C6 coefficients
Optional variables: "ts_vdw_econv_thr", "ts_vdw_isolated"
See A. Tkatchenko and M. Scheffler, Phys. Rev. Lett. 102, 073005 (2009)
'XDM', 'xdm': Exchange-hole dipole-moment model. Optional variables: "xdm_a1", "xdm_a2"
(implemented in PW only)
A. D. Becke and E. R. Johnson, J. Chem. Phys. 127, 154108 (2007)
A. Otero de la Roza, E. R. Johnson, J. Chem. Phys. 136, 174109 (2012)
Note that non-local functionals (eg vdw-DF) are NOT specified here but in "input_dft"
}
}
var london_s6 -type REAL {
default { 0.75 }
info {
global scaling parameter for DFT-D. Default is good for PBE.
}
}
var london_rcut -type REAL {
default { 200 }
info {
cutoff radius (a.u.) for dispersion interactions
}
}
var ts_vdw -type LOGICAL {
default { .FALSE. }
info {
OBSOLESCENT, same as vdw_corr='TS'
}
}
var ts_vdw_econv_thr -type REAL {
default { 1.D-6 }
info {
Optional: controls the convergence of the vdW energy (and forces). The default value
is a safe choice, likely too safe, but you do not gain much in increasing it
}
}
var ts_vdw_isolated -type LOGICAL {
default { .FALSE. }
info {
Optional: set it to .TRUE. when computing the Tkatchenko-Scheffler vdW energy
for an isolated (non-periodic) system.
}
}
var assume_isolated -type CHARACTER {
default { 'none' }
info {
Used to perform calculation assuming the system to be
isolated (a molecule of a clustr in a 3D supercell).
Currently available choices:
'none' (default): regular periodic calculation w/o any correction.
'makov-payne', 'm-p', 'mp' : the Makov-Payne correction to the
total energy is computed.
Theory:
G.Makov, and M.C.Payne,
"Periodic boundary conditions in ab initio
calculations" , Phys.Rev.B 51, 4014 (1995)
}
}
}
#
# namelist ELECTRONS
#
namelist ELECTRONS {
var electron_maxstep -type INTEGER {
default { 100 }
info {
maximum number of iterations in a scf step
}
}
var electron_dynamics -type CHARACTER {
default { 'none' }
info {
set how electrons should be moved
'none' : electronic degrees of freedom (d.o.f.) are kept fixed
'sd' : steepest descent algorithm is used to minimize
electronic d.o.f.
'damp' : damped dynamics is used to propagate electronic d.o.f.
'verlet' : standard Verlet algorithm is used to propagate
electronic d.o.f.
'cg' : conjugate gradient is used to converge the
wavefunction at each ionic step. 'cg' can be used
interchangeably with 'verlet' for a couple of ionic
steps in order to "cool down" the electrons and
return them back to the Born-Oppenheimer surface.
Then 'verlet' can be restarted again. This procedure
is useful when electronic adiabaticity in CP is lost
yet the ionic velocities need to be preserved.
}
}
var conv_thr -type REAL {
default { 1.D-6 }
info {
Convergence threshold for selfconsistency:
estimated energy error < conv_thr
}
}
var niter_cg_restart -type INTEGER {
default { 20 }
info {
frequency in iterations for which the conjugate-gradient algorithm
for electronic relaxation is restarted
}
}
var efield -type REAL {
default { 0.D0 }
info {
Amplitude of the finite electric field (in a.u.;
1 a.u. = 51.4220632*10^10 V/m). Used only if tefield=.TRUE.
}
}
var epol -type INTEGER {
default { 3 }
info {
direction of the finite electric field (only if tefield == .TRUE.)
In the case of a PARALLEL calculation only the case epol==3
is implemented
}
}
var emass -type REAL {
default { 400.D0 }
info {
effective electron mass in the CP Lagrangian, in atomic units
( 1 a.u. of mass = 1/1822.9 a.m.u. = 9.10939 * 10^-31 kg )
}
}
var emass_cutoff -type REAL {
default { 2.5D0 }
info {
mass cut-off (in Rydberg) for the Fourier acceleration
effective mass is rescaled for "G" vector components with
kinetic energy above "emass_cutoff"
}
}
var orthogonalization -type CHARACTER {
default { 'ortho' }
info {
selects the orthonormalization method for electronic wave
functions
'ortho' : use iterative algorithm - if it doesn't converge,
reduce the timestep, or use options ortho_max
and ortho_eps, or use Gram-Schmidt instead just
to start the simulation
'Gram-Schmidt' : use Gram-Schmidt algorithm - to be used ONLY in
the first few steps.
YIELDS INCORRECT ENERGIES AND EIGENVALUES.
}
}
var ortho_eps -type REAL {
default { 1.D-8 }
info {
tolerance for iterative orthonormalization
meaningful only if orthogonalization = 'ortho'
}
}
var ortho_max -type INTEGER {
default { 20 }
info {
maximum number of iterations for orthonormalization
meaningful only if orthogonalization = 'ortho'
}
}
var ortho_para -type INTEGER {
default { 0 }
status { OBSOLETE: use command-line option " -nd XX" instead }
info {
}
}
var electron_damping -type REAL {
default { 0.1D0 }
info {
damping frequency times delta t, optimal values could be
calculated with the formula :
SQRT( 0.5 * LOG( ( E1 - E2 ) / ( E2 - E3 ) ) )
where E1, E2, E3 are successive values of the DFT total energy
in a steepest descent simulations.
meaningful only if " electron_dynamics = 'damp' "
}
}
var electron_velocities -type CHARACTER {
info {
'zero' : restart setting electronic velocities to zero
'default' : restart using electronic velocities of the
previous run
'change_step' : restart simulation using electronic velocities of the
previous run, with rescaling due to the timestep change.
specify the old step via @ref tolp as in
tolp = 'old_time_step_value' in au.
Note that you may want to specify
@ref ion_velocities = 'change_step'
}
}
var electron_temperature -type CHARACTER {
default { 'not_controlled' }
info {
'nose' : control electronic temperature using Nose
thermostat. See also "fnosee" and "ekincw".
'rescaling' : control electronic temperature via velocities
rescaling.
'not_controlled' : electronic temperature is not controlled.
}
}
var ekincw -type REAL {
default { 0.001D0 }
info {
value of the average kinetic energy (in atomic units) forced
by the temperature control
meaningful only with " electron_temperature /= 'not_controlled' "
}
}
var fnosee -type REAL {
default { 1.D0 }
info {
oscillation frequency of the nose thermostat (in terahertz)
meaningful only with " electron_temperature = 'nose' "
}
}
var startingwfc -type CHARACTER {
default { 'random' }
info {
'atomic': start from superposition of atomic orbitals
(not yet implemented)
'random': start from random wfcs. See "ampre".
}
}
var tcg -type LOGICAL {
default { .FALSE. }
info {
if .TRUE. perform a conjugate gradient minimization of the
electronic states for every ionic step.
It requires Gram-Schmidt orthogonalization of the electronic
states.
}
}
var maxiter -type INTEGER {
default { 100 }
info {
maximum number of conjugate gradient iterations for
conjugate gradient minimizations of electronic states
}
}
var passop -type REAL {
default { 0.3D0 }
info {
small step used in the conjugate gradient minimization
of the electronic states.
}
}
var n_inner -type INTEGER {
default { 2 }
info {
number of internal cycles for every conjugate gradient
iteration only for ensemble DFT
}
}
var ninter_cold_restart -type INTEGER {
default { 1 }
info {
frequency in iterations at which a full inner cycle, only
for cold smearing, is performed
}
}
var lambda_cold -type REAL {
default { 0.03D0 }
info {
step for inner cycle with cold smearing, used when a not full
cycle is performed
}
}
var grease -type REAL {
default { 1.D0 }
info {
a number <= 1, very close to 1: the damping in electronic
damped dynamics is multiplied at each time step by "grease"
(avoids overdamping close to convergence: Obsolete ?)
grease = 1 : normal damped dynamics
}
}
var ampre -type REAL {
default { 0.D0 }
info {
amplitude of the randomization ( allowed values: 0.0 - 1.0 )
meaningful only if " startingwfc = 'random' "
}
}
}
#
# NAMELIST IONS
#
namelist IONS {
label {
input this namelist only if calculation = 'cp', 'relax', 'vc-relax', 'vc-cp', 'cp-wf', 'vc-cp-wf'
}
var ion_dynamics -type CHARACTER {
info {
Specify the type of ionic dynamics.
For constrained dynamics or constrained optimisations add the
CONSTRAINTS card (when the card is present the SHAKE algorithm is
automatically used).
'none' : ions are kept fixed
'sd' : steepest descent algorithm is used to minimize ionic
configuration
'cg' : conjugate gradient algorithm is used to minimize ionic
configuration
'damp' : damped dynamics is used to propagate ions
'verlet' : standard Verlet algorithm is used to propagate ions
}
}
var ion_positions -type CHARACTER {
default { 'default' }
info {
'default ' : if restarting, use atomic positions read from the
restart file; in all other cases, use atomic
positions from standard input.
'from_input' : restart the simulation with atomic positions read
from standard input, even if restarting.
}
}
var ion_velocities -type CHARACTER {
default { 'default' }
see { tempw }
info {
initial ionic velocities
'default' : restart the simulation with atomic velocities read
from the restart file
'change_step' : restart the simulation with atomic velocities read
from the restart file, with rescaling due to the
timestep change, specify the old step via @ref tolp
as in tolp = 'old_time_step_value' in au.
Note that you may want to specify
electron_velocities = 'change_step'
'random' : start the simulation with random atomic velocities
(see also variable @ref tempw)
'from_input' : restart the simulation with atomic velocities read
from standard input - see card 'ATOMIC_VELOCITIES'
BEWARE: tested only with electrons_dynamics='cg'
'zero' : restart the simulation with atomic velocities set
to zero
}
}
var ion_damping -type REAL {
default { 0.2D0 }
info {
damping frequency times delta t, optimal values could be
calculated with the formula :
SQRT( 0.5 * LOG( ( E1 - E2 ) / ( E2 - E3 ) ) )
where E1, E2, E3 are successive values of the DFT total energy
in a steepest descent simulations.
meaningful only if " ion_dynamics = 'damp' "
}
}
dimension ion_radius -start 1 -end ntyp -type REAL {
default { 0.5 a.u. for all species }
info {
ion_radius(i): pseudo-atomic radius of the i-th atomic species
used in Ewald summation. Typical values: between 0.5 and 2.
Results should NOT depend upon such parameters if their values
are properly chosen. See also "iesr".
}
}
var iesr -type INTEGER {
default { 1 }
info {
The real-space contribution to the Ewald summation is performed
on iesr*iesr*iesr cells. Typically iesr=1 is sufficient to have
converged results.
}
}
var ion_nstepe -type INTEGER {
default { 1 }
info {
number of electronic steps per ionic step.
}
}
var remove_rigid_rot -type LOGICAL {
default { .FALSE. }
info {
This keyword is useful when simulating the dynamics and/or the
thermodynamics of an isolated system. If set to true the total
torque of the internal forces is set to zero by adding new forces
that compensate the spurious interaction with the periodic
images. This allows for the use of smaller supercells.
BEWARE: since the potential energy is no longer consistent with
the forces (it still contains the spurious interaction with the
repeated images), the total energy is not conserved anymore.
However the dynamical and thermodynamical properties should be
in closer agreement with those of an isolated system.
Also the final energy of a structural relaxation will be higher,
but the relaxation itself should be faster.
}
}
var ion_temperature -type CHARACTER {
default { 'not_controlled' }
info {
'nose' : control ionic temperature using Nose-Hoover
thermostat see parameters "fnosep", "tempw",
"nhpcl", "ndega", "nhptyp"
'rescaling' : control ionic temperature via velocities
rescaling. see parameter "tolp"
'not_controlled' : ionic temperature is not controlled
}
}
var tempw -type REAL {
default { 300.D0 }
info {
value of the ionic temperature (in Kelvin) forced by the
temperature control.
meaningful only with " ion_temperature /= 'not_controlled' "
or when the initial velocities are set to 'random'
"ndega" controls number of degrees of freedom used in
temperature calculation
}
}
var fnosep -type REAL {
default { 1.D0 }
info {
oscillation frequency of the nose thermostat (in terahertz)
[note that 3 terahertz = 100 cm^-1]
meaningful only with " ion_temperature = 'nose' "
for Nose-Hoover chain one can set frequencies of all thermostats
( fnosep = X Y Z etc. ) If only first is set, the defaults for
the others will be same.
}
}
var tolp -type REAL {
default { 100.D0 }
info {
tolerance (in Kelvin) of the rescaling. When ionic temperature
differs from "tempw" more than "tolp" apply rescaling.
meaningful only with @ref ion_temperature = 'rescaling'
or with @ref ion_velocities='change_step', where it specifies
the old timestep
}
}
var nhpcl -type INTEGER {
default { 1 }
info {
number of thermostats in the Nose-Hoover chain
currently maximum allowed is 4
}
}
var nhptyp -type INTEGER {
default { 0 }
info {
type of the "massive" Nose-Hoover chain thermostat
nhptyp=1 uses a NH chain per each atomic type
nhptyp=2 uses a NH chain per atom, this one is useful
for extremely rapid equipartitioning (equilibration is a
different beast)
nhptyp=3 together with nhgrp allows fine grained thermostat
control
NOTE: if using more than 1 thermostat per system there will
be a common thermostat added on top of them all, to disable
this common thermostat specify nhptyp=-X instead of nhptyp=X
}
}
dimension nhgrp -start 1 -end ntyp -type INTEGER {
default { 0 }
info {
specifies which thermostat group to use for given atomic type
when >0 assigns all the atoms in this type to thermostat
labeled nhgrp(i), when =0 each atom in the type gets its own
thermostat. Finally, when <0, then this atomic type will have
temperature "not controlled". Example: HCOOLi, with types H (1), C(2), O(3), Li(4);
setting nhgrp={2 2 0 -1} will add a common thermostat for both H & C,
one thermostat per each O (2 in total), and a non-updated thermostat
for Li which will effectively make temperature for Li "not controlled"
}
}
dimension fnhscl -start 1 -end ntyp -type REAL {
default { (Nat_{total}-1)/Nat_{total} }
info {
these are the scaling factors to be used together with nhptyp=3 and nhgrp(i)
in order to take care of possible reduction in the degrees of freedom due to
constraints. Suppose that with the previous example HCOOLi, C-H bond is
constrained. Then, these 2 atoms will have 5 degrees of freedom in total instead
of 6, and one can set fnhscl={5/6 5/6 1. 1.}. This way the target kinetic energy
for H&C will become 6(kT/2)*5/6 = 5(kT/2). This option is to be used for
simulations with many constraints, such as rigid water with something else in there
}
}
var ndega -type INTEGER {
default { 0 }
info {
number of degrees of freedom used for temperature calculation
ndega <= 0 sets the number of degrees of freedom to
[3*nat-abs(ndega)], ndega > 0 is used as the target number
}
}
dimension tranp -start 1 -end ntyp -type LOGICAL {
see { amprp }
default { .false. }
info {
If .TRUE. randomize ionic positions for the
atomic type corresponding to the index.
}
}
dimension amprp -start 1 -end ntyp -type REAL {
see { amprp }
default { 0.D0 }
info {
amplitude of the randomization for the atomic type corresponding
to the index i ( allowed values: 0.0 - 1.0 ).
meaningful only if " tranp(i) = .TRUE.".
}
}
var greasp -type REAL {
default { 1.D0 }
info {
same as "grease", for ionic damped dynamics.
}
}
}
#
# namelist CELL
#
namelist CELL {
label {
input this namelist only if calculation = 'vc-relax', 'vc-cp', 'vc-cp-wf'
}
var cell_parameters -type CHARACTER {
info {
'default' : restart the simulation with cell parameters read
from the restart file or "celldm" if
"restart = 'from_scratch'"
'from_input' : restart the simulation with cell parameters
from standard input.
( see the card 'CELL_PARAMETERS' )
}
}
var cell_dynamics -type CHARACTER {
default { 'none' }
info {
set how cell should be moved
'none' : cell is kept fixed
'sd' : steepest descent algorithm is used to optimise the
cell
'damp-pr' : damped dynamics is used to optimise the cell
( Parrinello-Rahman method ).
'pr' : standard Verlet algorithm is used to propagate
the cell ( Parrinello-Rahman method ).
}
}
var cell_velocities -type CHARACTER {
info {
'zero' : restart setting cell velocity to zero
'default' : restart using cell velocity of the previous run
}
}
var cell_damping -type REAL {
default { 0.1D0 }
info {
damping frequency times delta t, optimal values could be
calculated with the formula :
SQRT( 0.5 * LOG( ( E1 - E2 ) / ( E2 - E3 ) ) )
where E1, E2, E3 are successive values of the DFT total energy
in a steepest descent simulations.
meaningful only if " cell_dynamics = 'damp' "
}
}
var press -type REAL {
default { 0.D0 }
info {
Target pressure [KBar] in a variable-cell md or relaxation run.
}
}
var wmass -type REAL {
default {
0.75*Tot_Mass/pi**2 for Parrinello-Rahman MD;
0.75*Tot_Mass/pi**2/Omega**(2/3) for Wentzcovitch MD
}
info {
Fictitious cell mass [amu] for variable-cell simulations
(both 'vc-md' and 'vc-relax')
}
}
var cell_factor -type REAL {
default { 1.2D0 }
info {
Used in the construction of the pseudopotential tables.
It should exceed the maximum linear contraction of the
cell during a simulation.
}
}
var cell_temperature -type CHARACTER {
default { 'not_controlled' }
info {
'nose' : control cell temperature using Nose thermostat
see parameters "fnoseh" and "temph".
'rescaling' : control cell temperature via velocities
rescaling.
'not_controlled' : cell temperature is not controlled.
}
}
var temph -type REAL {
default { 0.D0 }
info {
value of the cell temperature (in ???) forced
by the temperature control.
meaningful only with " cell_temperature /= 'not_controlled' "
}
}
var fnoseh -type REAL {
default { 1.D0 }
info {
oscillation frequency of the nose thermostat (in terahertz)
meaningful only with " cell_temperature = 'nose' "
}
}
var greash -type REAL {
default { 1.D0 }
info {
same as "grease", for cell damped dynamics
}
}
var cell_dofree -type CHARACTER {
default { 'all' }
info {
Select which of the cell parameters should be moved:
all = all axis and angles are moved
x = only the x component of axis 1 (v1_x) is moved
y = only the y component of axis 2 (v2_y) is moved
z = only the z component of axis 3 (v3_z) is moved
xy = only v1_x and v2_y are moved
xz = only v1_x and v3_z are moved
yz = only v2_y and v3_z are moved
xyz = only v1_x, v2_y, v3_z are moved
shape = all axis and angles, keeping the volume fixed
2Dxy = only x and y components are allowed to change
2Dshape = as above, keeping the area in xy plane fixed
volume = isotropic variations of v1_x, v2_y, v3_z, keeping
the shape fixed. Should be used only with ibrav=1.
}
}
}
#
# namelist PRESS_AI
#
namelist PRESS_AI {
label {
input this namelist only when tabps = .true.
}
var abivol -type LOGICAL {
default { .false. }
info {
.true. for finite pressure calculations
}
}
var abisur -type LOGICAL {
default { .false. }
info {
.true. for finite surface tension calculations
}
}
var P_ext -type REAL {
default { 0.D0 }
info {
external pressure in GPa
}
}
var pvar -type LOGICAL {
default { .false. }
info {
.true. for variable pressure calculations
pressure changes linearly with time:
Delta_P = (P_fin - P_in)/nstep
}
}
var P_in -type REAL {
default { 0.D0 }
info {
only if pvar = .true.
initial value of the external pressure (GPa)
}
}
var P_fin -type REAL {
default { 0.D0 }
info {
only if pvar = .true.
final value of the external pressure (GPa)
}
}
var Surf_t -type REAL {
default { 0.D0 }
info {
Surface tension (in a.u.; typical values 1.d-4 - 1.d-3)
}
}
var rho_thr -type REAL {
default { 0.D0 }
info {
threshold parameter which defines the electronic charge density
isosurface to compute the 'quantum' volume of the system
(typical values: 1.d-4 - 1.d-3)
(corresponds to alpha in PRL 94 145501 (2005))
}
}
var dthr -type REAL {
default { 0.D0 }
info {
thikness of the external skin of the electronic charge density
used to compute the 'quantum' surface
(typical values: 1.d-4 - 1.d-3; 50% to 100% of rho_thr)
(corresponds to Delta in PRL 94 145501 (2005))
}
}
}
#
# namelist WANNIER
#
namelist WANNIER {
label {
only if calculation = 'cp-wf', 'vc-cp-wf'
}
message {
Output files used by Wannier Function options are the following
fort.21: Used only when calwf=5, contains the full list of g-vecs.
fort.22: Used Only when calwf=5, contains the coeffs. corresponding
to the g-vectors in fort.21
fort.24: Used with calwf=3,contains the average spread
fort.25: Used with calwf=3, contains the individual Wannier
Function Spread of each state
fort.26: Used with calwf=3, contains the wannier centers along a
trajectory.
fort.27: Used with calwf=3 and 4, contains some general runtime
information from ddyn, the subroutine that actually
does the localization of the orbitals.
fort.28: Used only if efield=.TRUE. , contains the polarization
contribution to the total energy.
Also, The center of mass is fixed during the Molecular Dynamics.
BEWARE : THIS WILL ONLY WORK IF THE NUMBER OF PROCESSORS IS LESS THAN OR
EQUAL TO THE NUMBER OF STATES.
Nota Bene 1: For calwf = 5, wffort is not used. The
Wannier/Wave(function) coefficients are written to unit 22
and the corresponding g-vectors (basis vectors) are
written to unit 21. This option gives the g-vecs and
their coeffs. in reciprocal space, and the coeffs. are
complex. You will have to convert them to real space
if you want to plot them for visualization. calwf=1 gives
the orbital densities in real space, and this is usually
good enough for visualization.
}
var wf_efield -type LOGICAL {
default { .false. }
info {
If dynamics will be done in the presence of a field
}
}
var wf_switch -type LOGICAL {
default { .false. }
info {
Whether to turn on the field adiabatically (adiabatic switch)
if true, then nbeg is set to 0.
}
}
var sw_len -type INTEGER {
default { 1 }
info {
No. of iterations over which the field will be turned on
to its final value. Starting value is 0.0
If sw_len < 0, then it is set to 1.
If you want to just optimize structures on the presence of a
field, then you may set this to 1 and run a regular geometry
optimization.
}
}
vargroup -type REAL {
see { 0.D0 }
var efx0
var efy0
var efz0
info {
Initial values of the field along x, y, and z directions
}
}
vargroup -type REAL {
see { 0.D0 }
var efx1
var efy1
var efz1
info {
Final values of the field along x, y, and z directions
}
}
var wfsd -type INTEGER {
default { 1 }
info {
Localization algorithm for Wannier function calculation:
wfsd=1 Damped Dynamics
wfsd=2 Steepest-Descent / Conjugate-Gradient
wfsd=3 Jocobi Rotation
Remember, this is consistent with all the calwf options
as well as the tolw (see below).
Not a good idea to Wannier dynamics with this if you are
using restart='from_scratch' option, since the spreads
converge fast in the beginning and ortho goes bananas.
}
}
var wfdt -type REAL {
default { 5.D0 }
info {
The minimum step size to take in the SD/CG direction
}
}
var maxwfdt -type REAL {
default { 0.3D0 }
info {
The maximum step size to take in the SD/CG direction
The code calculates an optimum step size, but that may be
either too small (takes forever to converge) or too large
(code goes crazy) . This option keeps the step size between
wfdt and maxwfdt. In my experience 0.1 and 0.5 work quite
well. (but don't blame me if it doesn't work for you)
}
}
var nit -type INTEGER {
default { 10 }
info {
Number of iterations to do for Wannier convergence.
}
}
var nsd -type INTEGER {
default { 10 }
info {
Out of a total of NIT iterations, NSD will be Steepest-Descent
and ( nit - nsd ) will be Conjugate-Gradient.
}
}
var wf_q -type REAL {
default { 1500.D0 }
info {
Fictitious mass of the A matrix used for obtaining
maximally localized Wannier functions. The unitary
transformation matrix U is written as exp(A) where
A is a anti-hermitian matrix. The Damped-Dynamics is performed
in terms of the A matrix, and then U is computed from A.
Usually a value between 1500 and 2500 works fine, but should
be tested.
}
}
var wf_friction -type REAL {
default { 0.3D0 }
info {
Damping coefficient for Damped-Dynamics.
}
}
var nsteps -type INTEGER {
default { 20 }
info {
Number of Damped-Dynamics steps to be performed per CP
iteration.
}
}
var tolw -type REAL {
default { 1.D-8 }
info {
Convergence criterion for localization.
}
}
var adapt -type LOGICAL {
default { .true. }
info {
Whether to adapt the damping parameter dynamically.
}
}
var calwf -type INTEGER {
default { 3 }
info {
Wannier Function Options, can be 1,2,3,4,5
1. Output the Wannier function density, nwf and wffort
are used for this option. see below.
2. Output the Overlap matrix O_i,j=<w_i|exp{iGr}|w_j>. O is
written to unit 38. For details on how O is constructed,
see below.
3. Perform nsteps of Wannier dynamics per CP iteration, the
orbitals are now Wannier Functions, not Kohn-Sham orbitals.
This is a Unitary transformation of the occupied subspace
and does not leave the CP Lagrangian invariant. Expectation
values remain the same. So you will **NOT** have a constant
of motion during the run. Don't freak out, its normal.
4. This option starts for the KS states and does 1 CP iteration
and nsteps of Damped-Dynamics to generate maximally
localized wannier functions. Its useful when you have the
converged KS groundstate and want to get to the converged
Wannier function groundstate in 1 CP Iteration.
5. This option is similar to calwf 1, except that the output is
the Wannier function/wavefunction, and not the orbital
density. See nwf below.
}
}
var nwf -type INTEGER {
default { 0 }
info {
This option is used with calwf 1 and calwf 5. with calwf=1,
it tells the code how many Orbital densities are to be
output. With calwf=5, set this to 1(i.e calwf=5 only writes
one state during one run. so if you want 10 states, you have
to run the code 10 times). With calwf=1, you can print many
orbital densities in a single run.
See also the PLOT_WANNIER card for specifying the states to
be printed.
}
}
var wffort -type INTEGER {
default { 40 }
info {
This tells the code where to dump the orbital densities. Used
only with CALWF=1. for e.g. if you want to print 2 orbital
densities, set calwf=1, nwf=2 and wffort to an appropriate
number (e.g. 40) then the first orbital density will be
output to fort.40, the second to fort.41 and so on. Note that
in the current implementation, the following units are used
21,22,24,25,26,27,28,38,39,77,78 and whatever you define as
ndr and ndw. so use number other than these.
}
}
var writev -type LOGICAL {
default { .false. }
info {
Output the charge density (g-space) and the list of g-vectors
This is useful if you want to reconstruct the electrostatic
potential using the Poisson equation. If .TRUE. then the
code will output the g-space charge density and the list
if G-vectors, and STOP.
Charge density is written to : CH_DEN_G_PARA.ispin (1 or 2
depending on the number of spin types) or CH_DEN_G_SERL.ispin
depending on if the code is being run in parallel or serial
G-vectors are written to G_PARA or G_SERL.
}
}
var exx_neigh -type INTEGER {
default { 60 }
info {
An initial guess on the maximum number of neighboring (overlapping) Wannier functions.
}
}
var exx_dis_cutoff -type REAL {
default { 8.0 }
info {
Radial cutoff distance (in bohr) for including overlapping Wannier function pairs
in EXX calculations.
}
}
var exx_poisson_eps -type REAL {
default { 1.0D-6 }
info {
Poisson solver convergence criterion during computation of the EXX potential.
}
}
var exx_ps_rcut_self -type REAL {
default { 6.0 }
info {
Radial cutoff distance (in bohr) to compute the self EXX energy.
This distance determines the radius of the Poisson sphere centered at
a given Wannier function center, and should be large enough to cover
the majority of the orbital charge density.
}
}
var exx_ps_rcut_pair -type REAL {
default { 5.0 }
info {
Radial cutoff distance (in bohr) to compute the pair EXX energy.
This distance determines the radius of the Poisson sphere centered at
the midpoint of two overlapping Wannier functions, and should be
large enough to cover the majority of the orbital overlap charge density.
This parameter can generally be chosen as smaller than exx_ps_rcut_self.
}
}
var exx_me_rcut_self -type REAL {
default { 10.0 }
info {
Radial cutoff distance (in bohr) for the multipole-expansion sphere
centered at a given Wannier function center.
The far-field self EXX potential in this sphere is generated with
multipole expansion of the orbital charge density.
}
}
var exx_me_rcut_pair -type REAL {
default { 7.0 }
info {
Radial cutoff distance (in bohr) for the multipole-expansion sphere
centered at the midpoint of two overlapping Wannier functions.
The far-field pair EXX potential in this sphere is generated with
a multipole expansion of the orbital overlap charge density.
This parameter can generally be chosen as smaller than exx_me_rcut_self.
}
}
}
#
# card ATOMIC_SPECIES
#
card ATOMIC_SPECIES {
syntax {
table atomic_species {
rows -start 1 -end ntyp {
col X -type CHARACTER {
info {
label of the atom. Acceptable syntax:
chemical symbol X (1 or 2 characters, case-insensitive)
or chemical symbol plus a number or a letter, as in
"Xn" (e.g. Fe1) or "X_*" or "X-*" (e.g. C1, C_h;
max total length cannot exceed 3 characters)
}
}
col Mass_X -type REAL {
info {
mass of the atomic species [amu: mass of C = 12]
not used if calculation='scf', 'nscf', 'bands'
}
}
col PseudoPot_X -type CHARACTER {
info {
File containing PP for this species.
The pseudopotential file is assumed to be in the new UPF format.
If it doesn't work, the pseudopotential format is determined by
the file name:
*.vdb or *.van Vanderbilt US pseudopotential code
*.RRKJ3 Andrea Dal Corso's code (old format)
none of the above old PWscf norm-conserving format
}
}
}
}
}
}
#
# card ATOMIC_POSITIONS
#
card ATOMIC_POSITIONS {
flag atompos_unit -use optional {
enum { alat | bohr | angstrom | crystal }
default { (DEPRECATED) bohr }
info {
alat : atomic positions are in cartesian coordinates,
in units of the lattice parameter (either
celldm(1) or A).
bohr : atomic positions are in cartesian coordinate,
in atomic units (i.e. Bohr).
If no option is specified, 'bohr' is assumed;
not specifying units is DEPRECATED and will no
longer be allowed in the future
angstrom: atomic positions are in cartesian coordinates,
in Angstrom
crystal : atomic positions are in crystal coordinates, i.e.
in relative coordinates of the primitive lattice
vectors as defined either in card CELL_PARAMETERS
or via the ibrav + celldm / a,b,c... variables
}
}
choose {
when -test "calculation == 'bands' OR calculation == 'nscf'" {
message {
Specified atomic positions will be IGNORED and those from the
previous scf calculation will be used instead !!!
}
}
elsewhen {
syntax {
table atomic_coordinates {
rows -start 1 -end nat {
col X -type CHARACTER {
info { label of the atom as specified in ATOMIC_SPECIES }
}
colgroup -type REAL {
info { atomic positions }
col x
col y
col z
}
optional {
colgroup -type INTEGER {
info {
component i of the force for this atom is multiplied by if_pos(i),
which must be either 0 or 1. Used to keep selected atoms and/or
selected components fixed in MD dynamics or
structural optimization run.
}
default { 1 }
col if_pos(1)
col if_pos(2)
col if_pos(3)
}
}
}
}
}
}
}
}
#
# ATOMIC_VELOCITIES
#
card ATOMIC_VELOCITIES {
flag atomvel_type -use optional {
enum { a.u }
}
label {
Optional card, reads velocities from standard input
}
message {
when starting with ion_velocities="from_input" it is convenient
to perform a few steps (~5-10) with a small time step (0.5 a.u.).
The velocities must be expressed using the same length units
indicated in the card ATOMIC_POSITIONS, divided by time
in atomic units.
}
syntax {
table atomic_velocities {
rows -start 1 -end nat {
col V -type CHARACTER {
info { label of the atom as specified in ATOMIC_SPECIES }
}
colgroup -type REAL {
info { atomic velocities along x y and z direction}
col vx
col vy
col vz
}
}
}
}
}
#
# CELL_PARAMETERS
#
card CELL_PARAMETERS {
flag lattice_type -use optional {
enum { bohr | angstrom | alat }
info {
'bohr'/'angstrom': lattice vectors in bohr radii / angstrom.
'alat' / nothing specified: lattice vectors in units or the
lattice parameter (either celldm(1) or a). Not specifing
units is DEPRECATED and will not be allowed in the future.
If nothing specified and no lattice parameter specified,
'bohr' is assumed - DEPRECATED, will no longer be allowed
}
}
label {
Optional card, needed only if ibrav = 0 is specified, ignored otherwise !
}
syntax {
table lattice {
cols -start 1 -end 3 {
rowgroup -type REAL {
info {
Crystal lattice vectors:
v1(1) v1(2) v1(3) ... 1st lattice vector
v2(1) v2(2) v2(3) ... 2nd lattice vector
v3(1) v3(2) v3(3) ... 3rd lattice vector
}
row v1
row v2
row v3
}
}
}
}
}
#
# REF_CELL_PARAMETERS
#
card REF_CELL_PARAMETERS {
flag lattice_type -use optional {
enum { bohr | angstrom }
info {
bohr / angstrom: reference cell parameters in bohr radii / angstrom.
To mimic a constant effective planewave kinetic energy (ecfixed) during a
variable-cell calculation, the specified reference cell has to be large enough
such that the individual cell vector lengths of the fluctuating cell do not
exceed the corresponding reference lattice vector lengths during the entire
calculation. The cost of the calculation will increase with the increasing
size of the reference cell. The user must test for the proper reference cell
parameters.
The reference cell parameters should be used in conjunction with q2sigma,
qcutz, and ecfixed. See q2sigma for more information about mimicking constant
effective planewave kinetic energy (ecfixed) during variable-cell calculations.
The reference cell parameters should be chosen as an isotropic scaling of the
initial cell of the system. This means that the reference cell should have
the same shape as the initial simulatoin cell. The reference cell parameters should
NOT be changed throughout a given simulatoin. Typically, 2%-10% scaling of
the unit cell vectors are sufficient. However, the cell fluctuations depend on
the system and the thermodynamic conditions. So again user must test for the proper
choice of reference cell parameters.
}
}
label {
Optional card, needed only if one wants to do variable cell calculations accurately.
The reference cell generates additional buffer planewaves.
}
syntax {
table lattice {
cols -start 1 -end 3 {
rowgroup -type REAL {
info {
REF_CELL_PARAMETERS { bohr | angstrom }
v1(1) v1(2) v1(3) ... 1st reference lattice vector
v2(1) v2(2) v2(3) ... 2nd reference lattice vector
v3(1) v3(2) v3(3) ... 3rd reference lattice vector
}
row v1
row v2
row v3
}
}
}
}
}
#
# CONSTRAINTS
#
card CONSTRAINTS {
label {
Optional card, used for constrained dynamics or constrained optimisations
}
message {
When this card is present the SHAKE algorithm is automatically used.
}
syntax {
line {
var nconstr -type INTEGER {
info { Number of constraints. }
}
optional {
var constr_tol -type REAL {
info { Tolerance for keeping the constraints satisfied. }
}
}
}
table constraints_table {
rows -start 1 -end nconstr {
col constr_type -type CHARACTER {
info {
Type of constrain :
'type_coord' : constraint on global coordination-number, i.e. the
average number of atoms of type B surrounding the
atoms of type A. The coordination is defined by
using a Fermi-Dirac.
(four indexes must be specified).
'atom_coord' : constraint on local coordination-number, i.e. the
average number of atoms of type A surrounding a
specific atom. The coordination is defined by
using a Fermi-Dirac.
(four indexes must be specified).
'distance' : constraint on interatomic distance
(two atom indexes must be specified).
'planar_angle' : constraint on planar angle
(three atom indexes must be specified).
'torsional_angle' : constraint on torsional angle
(four atom indexes must be specified).
'bennett_proj' : constraint on the projection onto a given direction
of the vector defined by the position of one atom
minus the center of mass of the others.
( Ch.H. Bennett in Diffusion in Solids, Recent
Developments, Ed. by A.S. Nowick and J.J. Burton,
New York 1975 ).
}
}
colgroup {
col constr(1)
col constr(2)
conditional {
col constr(3)
col constr(4)
}
info {
These variables have different meanings
for different constraint types:
'type_coord' : constr(1) is the first index of the
atomic type involved
constr(2) is the second index of the
atomic type involved
constr(3) is the cut-off radius for
estimating the coordination
constr(4) is a smoothing parameter
'atom_coord' : constr(1) is the atom index of the
atom with constrained coordination
constr(2) is the index of the atomic
type involved in the coordination
constr(3) is the cut-off radius for
estimating the coordination
constr(4) is a smoothing parameter
'distance' : atoms indices object of the
constraint, as they appear in
the 'ATOMIC_POSITION' CARD
'planar_angle', 'torsional_angle' : atoms indices object of the
constraint, as they appear in the
'ATOMIC_POSITION' CARD (beware the
order)
'bennett_proj' : constr(1) is the index of the atom
whose position is constrained.
constr(2:4) are the three coordinates
of the vector that specifies the
constraint direction.
}
}
optional {
col constr_target -type REAL {
info {
Target for the constrain ( angles are specified in degrees ).
This variable is optional.
}
}
}
}
}
}
}
#
# card OCCUPATIONS
#
card OCCUPATIONS {
label { Optional card, used only if occupations = 'from_input', ignored otherwise ! }
syntax {
table occupations_table {
cols -start 1 -end nbnd {
row f_inp1 -type REAL {
info {
Occupations of individual states (MAX 10 PER LINE).
For spin-polarized calculations, these are majority spin states.
}
}
conditional {
row f_inp2 -type REAL {
info {
Occupations of minority spin states (MAX 10 PER LINE)
To be specified only for spin-polarized calculations.
}
}
}
}
}
}
}
#
# card ATOMIC_FORCES
#
card ATOMIC_FORCES {
label { Optional card used to specify external forces acting on atoms }
syntax {
table atomic_forces {
rows -start 1 -end nat {
col X -type CHARACTER {
info { label of the atom as specified in ATOMIC_SPECIES }
}
colgroup -type REAL {
info { external force on atom X (cartesian components, Ha/a.u. units)
}
col fx
col fy
col fz
}
}
}
}
}
#
# PLOT_WANNIER
#
card PLOT_WANNIER {
label {
Optional card, indices of the states that have to be printed (only for calf=1 and calf=5).
}
syntax {
table state_index {
rows -start 1 -end nwf {
col iwf -type INTEGER {
info {
These are the indices of the states that you want to output.
Also used with calwf = 1 and 5. If calwf = 1, then you need
nwf indices here (each in a new line). If CALWF=5, then just
one index in needed.
}
}
}
}
}
}
#
# AUTOPILOT
#
card AUTOPILOT {
label {
Optional card, changes some variables on the fly of the calculation.
Notice that the rules has to be ordered in with time step and the Card has
to be terminated with "ENDRULES"
}
syntax {
table state_index {
rows -start 1 -end nevent {
col pilot_rule -type RULE {
info {
To set up a rule, one can add the scheduled steps with on_step and
separate the corresponding change in parameters with a column.
See a simple example bellow:
AUTOPILOT
on_step = 31 : dt = 5.0
on_step = 91 : iprint = 100
on_step = 91 : isave = 100
on_step = 191 : ion_dynamics = 'damp'
on_step = 191 : electron_damping = 0.00
on_step = 691 : ion_temperature = 'nose'
on_step = 691 : tempw = 150.0
ENDRULES
}
}
}
}
}
}
}