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!
! Copyright (C) 2001-2005 Quantum-ESPRESSO group
! This file is distributed under the terms of the
! GNU General Public License. See the file `License'
! in the root directory of the present distribution,
! or http://www.gnu.org/copyleft/gpl.txt .
!
!--------------------------------------------------------------------------
!
MODULE basis
!
! ... The variables needed to describe the atoms in the unit cell
!
SAVE
!
INTEGER :: &
natomwfc ! number of starting wavefunctions
CHARACTER(LEN=30) :: & ! 'alat', 'crystal', 'angstrom', 'bohr'
atomic_positions ! specifies how input coordinates are given
CHARACTER(LEN=6) :: &
startingwfc , &! 'random' or 'atomic' or 'file'
startingpot , &! 'atomic' or 'file'
startingconfig ! 'input' or 'file'
!
END MODULE basis
!
!
MODULE gvect
!
! ...The variables describing the reciprocal lattice vectors
!
USE kinds, ONLY : DP
USE reciprocal_vectors, ONLY : ig_l2g, sortedig_l2g
!
SAVE
!
INTEGER :: &
ngm, &! number of g vectors
ngm_g, &! global number of g vectors (sum over all processors)
ngm_l, &! the local number of g vectors (only present processor)
gstart, &! first nonzero g vector
nr1, &! fft dimension along x
nr2, &! fft dimension along y
nr3, &! fft dimension along z
nrx1, &! maximum fft dimension along x
nrx2, &! maximum fft dimension along y
nrx3, &! maximum fft dimension along z
nrxx, &! maximum total fft
ngl ! number of |g| shells
!INTEGER, ALLOCATABLE :: &
! ig_l2g(:) !"l2g" means local to global, this array convert a local
! ! G-vector index into the global index, in other words
! ! the index of the G-v. in the overall array of G-vectors
INTEGER, ALLOCATABLE, TARGET :: &
nl(:), &! correspondence fft <-> array of G vectors
nlm(:), &! same for gamma point calculation
igtongl(:) ! correspondence shells of G <-> G
REAL(DP), ALLOCATABLE, TARGET :: &
g(:,:), &! coordinates of G vectors
gg(:) ! modulus G^2 of G vectors
! G vectors are in order of increasing |G|
REAL(DP) :: &
ecutwfc ! energy cut-off
REAL(DP), POINTER :: &
gl(:) ! the modulus of g in each shell
REAL (DP) :: &
gcutm, &! cut-off for G vectors
dual, &! link between G of wavefunctions and charge
ecfixed, &!
qcutz, &! For the modified Ekin functional
q2sigma !
complex(DP), ALLOCATABLE :: &
eigts1(:,:), &!
eigts2(:,:), &! the phases e^{-iG*tau_s}
eigts3(:,:) !
INTEGER, ALLOCATABLE :: &
ig1(:), &!
ig2(:), &! the indices of G components
ig3(:) !
!
END MODULE gvect
!
!
MODULE gsmooth
!
! ... the variables for the smooth mesh of the wavefunction. It can
! ... be different from the large mesh if dual > 4
!
USE kinds, ONLY : DP
!
SAVE
!
INTEGER :: &
ngms, &! the number of smooth G vectors
ngms_g, &! the global number of smooth G vectors
! (sum over all processors)
ngms_l, &! the local number of smooth G vectors
! (only present processor)
nr1s, &!
nr2s, &! the dimension of the smooth grid
nr3s, &!
nrx1s, &! maximum dimension of the smooth grid
nrx2s, &! maximum dimension of the smooth grid
nrx3s, &! maximum dimension of the smooth grid
nrxxs ! the total dimension of the smooth grid
INTEGER, POINTER :: &
nls(:), &! the correspondence G <-> smooth mesh
nlsm(:) ! the same for gamma point calculation
LOGICAL :: &
doublegrid ! .TRUE. if we use a double grid
REAL(DP) :: &
gcutms ! the cut-off of the smooth mesh
!
END MODULE gsmooth
!
!
MODULE klist
!
! ... The variables for the k-points
!
USE kinds, ONLY : DP
USE parameters, ONLY : npk
!
SAVE
!
REAL(DP) :: &
xk(3,npk), &! coordinates of k points
wk(npk), &! weight of k points
xqq(3), &! coordinates of q point (used with iswitch=-2)
degauss, &! smearing parameter
nelec, &! number of electrons
nelup, &! number of spin-up electrons (if two_fermi_energies=t)
neldw, &! number of spin-dw electrons (if two_fermi_energies=t)
tot_charge, &! total charge
b_length ! length of the b vectors
INTEGER :: &
ngk(npk), &! number of plane waves for each k point
nks, &! number of k points in this pool
nkstot, &! total number of k points
ngauss, &! type of smearing technique
tot_magnetization, &! nelup-neldw >= 0 (negative value means unspecified)
multiplicity ! spin multiplicity
LOGICAL :: &
lgauss, &! if .TRUE.: use gaussian broadening
lxkcry, &! if .TRUE.:k-pnts in cryst. basis accepted in input
lcart, &! if .TRUE.: b vectors in cartesian coordinates
two_fermi_energies ! if .TRUE.: nelup and neldw set ef_up and ef_dw
! separately
!
END MODULE klist
!
!
MODULE lsda_mod
!
! ... The variables needed for the lsda calculation
!
USE kinds, ONLY : DP
USE parameters, ONLY : ntypx, npk
!
SAVE
!
LOGICAL :: &
lsda
REAL(DP) :: &
magtot, &! total magnetization
absmag, &! total absolute magnetization
starting_magnetization(ntypx) ! the magnetization used to start with
INTEGER :: &
nspin, &! number of spin polarization: 2 if lsda, 1 other
current_spin, &! spin of the current kpoint
isk(npk) ! for each k-point: 1=spin up, 2=spin down
!
END MODULE lsda_mod
!
!
MODULE ktetra
!
! ... The variables for the tetrahedron method
!
SAVE
!
INTEGER :: &
nk1, nk2, nk3, &! the special-point grid
k1, k2, k3, &! the offset from the origin
ntetra ! number of tetrahedra
INTEGER, ALLOCATABLE :: &
tetra(:,:) ! index of k-points in a given tetrahedron
! shape (4,ntetra)
LOGICAL :: &
ltetra ! if .TRUE.: use tetrahedron method
!
END MODULE ktetra
!
!
MODULE symme
!
! ... The variables needed to describe the symmetry properties
!
SAVE
!
INTEGER :: &
s(3,3,48), &! simmetry matrices
ftau(3,48), &! fractional translations
nsym ! number of symmetries
INTEGER :: &
t_rev(48) = 0 ! time reversal flag, for noncolinear magnetisation
INTEGER, ALLOCATABLE :: &
irt(:,:) ! symmetric atom for each atom and sym.op.
LOGICAL :: &
invsym ! if .TRUE. the system has inversion symmetry
!
END MODULE symme
!
!
MODULE pseud
!
! ... The variables describing pseudopotentials in analytical form
!
USE kinds, ONLY : DP
USE parameters, ONLY : npsx
!
SAVE
!
REAL(DP) :: &
cc(2,npsx), &! the coefficients of the erf functions
alpc(2,npsx), &! the alpha of the erf functions
zp(npsx), &! the charge of the pseudopotential
aps(6,0:3,npsx), &! the a_l coefficient
alps(3,0:3,npsx) ! the b_l coefficient
REAL(DP) :: &
a_nlcc(npsx), &! nonlinear core correction coefficients:
b_nlcc(npsx), &! rho_c(r) = (a_c + b_c*r^2) exp(-alpha_c*r^2)
alpha_nlcc(npsx) !
INTEGER :: &
nlc(npsx), &! number of erf functions
nnl(npsx), &! number of the gaussian functions
lmax(npsx), &! maximum angular momentum of the pseudopot
lloc(npsx) ! angular momentum of the part taken as local
!
END MODULE pseud
!
!
MODULE vlocal
!
! ... The variables needed for the local potential in reciprocal space
!
USE kinds, ONLY : DP
!
SAVE
!
COMPLEX(DP), ALLOCATABLE :: &
strf(:,:) ! the structure factor
REAL(DP), ALLOCATABLE :: &
vloc(:,:), &! the local potential for each atom type
vnew(:,:) ! V_out - V_in, needed in scf force correction
!
END MODULE vlocal
!
!
MODULE wvfct
!
! ... The variables needed to compute the band structure
!
USE kinds, ONLY : DP
!
SAVE
!
INTEGER :: &
npwx, &! maximum number of PW for wavefunctions
nbndx, &! max number of bands use in iterative diag
nbnd, &! number of bands
npw, &! the number of plane waves
current_k ! the index of k-point under consideration
INTEGER, ALLOCATABLE, TARGET :: &
igk(:), &! correspondence k+G <-> G
igk_l2g(:,:) ! correspondence local index k+G <-> global G index
! see also ig_l2g
REAL(DP), ALLOCATABLE :: &
et(:,:), &! eigenvalues of the hamiltonian
wg(:,:), &! the weight of each k point and band
g2kin(:) ! kinetic energy
LOGICAL :: &
gamma_only ! if .TRUE. only half G vectors are used
!
END MODULE wvfct
!
!
MODULE ener
!
! ... The variables needed to compute the energies
!
USE kinds, ONLY : DP
!
SAVE
!
REAL(DP) :: &
etot, &! the total energy of the solid
eband, &! the band energy
deband, &! correction for variational energy
ehart, &! the hartree energy
etxc, &! the exchange and correlation energy
vtxc, &! another exchange-correlation energy
etxcc, &! the nlcc exchange and correlation
ewld, &! the ewald energy
demet, &! correction for metals
ef, ef_up, ef_dw ! the fermi energy (up and dw if two_fermi_energies=.T.)
!
END MODULE ener
!
!
MODULE force_mod
!
! ... The variables for the first derivative of the energy
!
USE kinds, ONLY : DP
!
SAVE
!
REAL(DP), ALLOCATABLE :: &
force(:,:) ! the force on each atom
REAL(DP) :: &
sigma(3,3) ! the stress acting on the system
LOGICAL :: &
lforce, &! if .TRUE. compute the forces
lstres ! if .TRUE. compute the stress
!
END MODULE force_mod
!
!
MODULE scf
!
! ... The variables needed to define the self-consistent cycle
!
USE kinds, ONLY : DP
!
SAVE
!
REAL(DP), ALLOCATABLE :: &
rho(:,:), &! the charge density in real space
vr(:,:), &! the Hartree + xc potential in real space
vltot(:), &! the local potential in real space
vrs(:,:), &! the total pot. in real space (smooth grig)
rho_core(:) ! the core charge in real space
!
END MODULE scf
!
!
MODULE relax
!
! ... The variables used to control ionic relaxations
!
USE kinds, ONLY : DP
!
SAVE
!
LOGICAL :: & ! if .TRUE. start the structural optimization
restart_bfgs ! from the results of a previous run
REAL(DP) :: &
epse, &! threshold on total energy
epsf, &! threshold on forces
starting_diag_threshold, &! self-explanatory
starting_scf_threshold ! as above
!
END MODULE relax
!
!
MODULE cellmd
!
! ... The variables used to control cell relaxation
!
USE kinds, ONLY : DP
!
SAVE
!
REAL(DP) :: &
press, cmass, &! target pressure and cell mass,
at_old(3,3), &! the lattice vectors at the previous ste
omega_old, &! the cell volume at the previous step
cell_factor ! maximum expected (linear) cell contraction
! during relaxation/MD
INTEGER :: &
nzero, &! iteration # of last thermalization
ntimes, &! number of thermalization steps to be performed
ntcheck ! # of steps between thermalizations
LOGICAL :: lmovecell ! used in cell relaxation
!
CHARACTER(LEN=2) :: &
calc ! main switch for variable cell shape MD
! see readin, vcsmd and/or INPUT files
!
END MODULE cellmd
!
!
!
MODULE char
!
! ... The names of the system and of the symmetries
!
USE printout_base, ONLY: title ! title of the run
!
SAVE
!
CHARACTER(LEN=20) :: crystal ! type of the solid
CHARACTER(LEN=45) :: sname(48) ! name of the symmetries
!
END MODULE char
!
!
MODULE us
!
! ... These parameters are needed with the US pseudopotentials
!
USE kinds, ONLY : DP
!
SAVE
!
INTEGER :: &
nqxq, &! size of interpolation table
nqx ! number of interpolation points
REAL(DP), PARAMETER:: &
dq = 0.01D0 ! space between points in the pseudopotential tab.
REAL(DP), ALLOCATABLE :: &
qrad(:,:,:,:), &! radial FT of Q functions
tab(:,:,:), &! interpolation table for PPs
tab_at(:,:,:) ! interpolation table for atomic wfc
!
END MODULE us
!
!
MODULE ldaU
!
! ... The quantities needed in lda+U calculations
!
USE kinds, ONLY : DP
USE parameters, ONLY : lqmax, nspinx, ntypx
!
SAVE
!
COMPLEX(DP), ALLOCATABLE :: &
swfcatom(:,:), & ! orthogonalized atomic wfcs
swfcatom_nc(:,:,:) ! orthogonalized atomic wfcs noncollinear case
REAL(DP), ALLOCATABLE :: &
ns(:,:,:,:), &! the occupation matrix used in h_psi
nsnew(:,:,:,:) ! the occupation matrix computed by at
REAL(DP) :: &
d1(3,3,48), &! matrices for rotating spherical
d2(5,5,48), &! harmonics
d3(7,7,48), &!
eth, &! the (corrected) Hubbard contribution
Hubbard_U(ntypx), &! the Hubbard U
Hubbard_alpha(ntypx), &! the Hubbard alpha (used to calculate U)
starting_ns(lqmax,nspinx,ntypx) !
INTEGER :: &
niter_with_fixed_ns, &! no. of iterations with fixed ns
Hubbard_l(ntypx), &! the agular momentum of Hubbard states
Hubbard_lmax ! maximum agular momentum of Hubbard states
LOGICAL :: &
lda_plus_u, &! .TRUE. if lda+u calculation is performed
conv_ns ! .TRUE. if ns are converged
CHARACTER(LEN=30) :: & ! 'atomic', 'ortho-atomic', 'file'
U_projection ! specifies how input coordinates are given
!
END MODULE ldaU
!
!
MODULE extfield
!
! ... The quantities needed in calculations with external field
!
USE kinds, ONLY : DP
!
SAVE
!
LOGICAL :: &
tefield, &! if .TRUE. a finite electric field is added to the
! local potential
dipfield ! if .TRUE. the dipole field is subtracted
INTEGER :: &
edir ! direction of the field
REAL(DP) :: &
emaxpos, &! position of the maximum of the field (0<emaxpos<1)
eopreg, &! amplitude of the inverse region (0<eopreg<1)
eamp, &! field amplitude (in a.u.) (1 a.u. = 51.44 10^11 V/m)
etotefield ! energy correction due to the field
REAL(DP), ALLOCATABLE :: &
forcefield(:,:)
!
END MODULE extfield
!
!
MODULE sticks
!
! ... data structure containing all information
! ... about fft data distribution for a given
! ... potential grid, and its wave functions sub-grid.
!
USE fft_types, ONLY : fft_dlay_descriptor
!
SAVE
!
TYPE ( fft_dlay_descriptor ) :: dfftp ! dense grid
TYPE ( fft_dlay_descriptor ) :: dffts ! smooth grid
!
END MODULE sticks
!
!
!
MODULE fixed_occ
!
! ... The quantities needed in calculations with fixed occupations
!
USE kinds, ONLY : DP
USE parameters, ONLY : nbndxx, nspinx
!
SAVE
!
REAL(DP) :: &
f_inp(nbndxx,nspinx) ! the occupations for each spin
LOGICAL :: &
tfixed_occ ! if .TRUE. the occupations are fixed.
!
END MODULE fixed_occ
MODULE spin_orb
USE kinds, ONLY: DP
USE parameters, ONLY : lmaxx, npsx
SAVE
LOGICAL :: &
lspinorb, & ! if .TRUE. this is a spin-orbit calculation
domag, & ! if .TRUE. magnetization is computed
so(npsx) ! for each pseudo tells if it is spin-orbit
COMPLEX (DP) :: rot_ylm(2*lmaxx+1,2*lmaxx+1) ! transform real
! spherical harmonics into complex ones
COMPLEX (DP), ALLOCATABLE :: fcoef(:,:,:,:,:) ! function needed to
! account for spinors.
END MODULE spin_orb
!
!
MODULE bp
USE kinds, ONLY: DP
!
! ... The variables needed for the Berry phase polarization calculation
!
SAVE
!
LOGICAL :: &
lberry, & ! if .TRUE., calculate polarization
lelfield ! if .TRUE. static homogeneous electric field
INTEGER :: &
gdir, &! G-vector for polarization calculation
nppstr, &! number of k-points (parallel vector)
nberrycyc !numer of cycles for cobergence in electric field without changing the selfconsistent charge
REAL(DP) :: efield ! electric field intensity in a.u.
COMPLEX(DP), ALLOCATABLE , TARGET :: evcel(:,:) ! wave function for calculating the electric field operator
!
END MODULE bp
!
MODULE pwcom
!
USE constants, ONLY : e2, rytoev, amconv, uakbar, pi, tpi, fpi
USE cell_base, ONLY : celldm, at, bg, alat, omega, tpiba, tpiba2, &
ibrav, symm_type
! TEMP
USE uspp
! TEMP
USE basis
USE gvect
USE gsmooth
USE klist
USE lsda_mod
USE ktetra
USE symme
USE pseud
USE vlocal
USE wvfct
USE ener
USE force_mod
USE scf
USE relax
USE cellmd
USE char
USE us
USE ldaU
USE extfield
USE sticks
USE bp
USE fixed_occ
USE spin_orb
USE bp
!
END MODULE pwcom
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