mirror of https://gitlab.com/QEF/q-e.git
122 lines
5.4 KiB
Plaintext
122 lines
5.4 KiB
Plaintext
phonon input cards are as follows:
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card 1 title_ph (a line that is reprinted on output)
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namelist "inputph"
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variable meaning default value
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amass(ntyp) atomic mass [amu] of each atomic type 0
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If not specified, masses are read from data file
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outdir scratch directory './'
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prefix prepended to input/output filenames 'pwscf'
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must be the same used in the calculation
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of unperturbed system
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niter_ph maximum number of iterations in a scf step 50
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tr2_ph threshold for selfconsistency 1e-10
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alpha_mix(niter) mixing factor (for each iteration) for alpha_mix(1)=0.7
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updating the scf potential:
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vnew(in) = alpha_mix*vold(out) + (1-alpha_mix)*vold(in)
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nmix_ph number of iterations used in potential mixing 4
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iverbosity iverbosity=0 short output, iverbosity=1 verbose output 0
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reduce_io reduce I/O to the strict minimum .false.
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max_seconds maximum allowed run time before the job stops smoothly 1.d7
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fildyn file where the dynamical matrix is written 'matdyn'
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fildrho file where the charge density responses are written ' '
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filelph file where electron-phonon matrix elements are written ' '
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fildvscf file where the the potential variation is written ' '
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(for later use in electron-phonon calculation)
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epsil if .true. in a q=0 calculation for a non metal the .false.
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macroscopic dielectric constant of the system is
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computed. Do not set epsil to .true. if you have a
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metallic system or q/=0: the code will complain and stop
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trans if .true. the phonons are computed .true.
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If trans.and.epsil effective charges are calculated
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lraman if .true. calculate nonresonant Raman coefficients .false.
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using second-order response as in:
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M. Lazzeri and F. Mauri, Phys. Rev. Lett. 90, 036401 (2003)
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Optional variables for Raman:
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eth_rps threshold for calculation of Pc R |psi> 1.0d-9
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eth_ns threshold for non-scf wavefunction calculation 1.0e-12
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dek delta_xk used for wavefunction derivation wrt k 1.0e-3
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recover if .true. restart from an interrupted run .false.
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elph if .true. electron-phonon lambda coeffs are computed .false.
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For metals only, requires gaussian smearing.
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If elph.and.trans, the lambdas are calculated in the same
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run, using the same k-point grid for phonons and lambdas
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If elph.and..not.trans, the lambdas are calculated using
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previously saved DeltaVscf in fildvscf, previously saved
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dynamical matrix, and the present punch file. This allows
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the use of a different (larger) k-point grid.
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zue if .true. in a q=0 calculation for a non metal the
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effective charges are computed from the phonon
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density responses. Note that if trans.and.epsil
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effective charges are calculated using a different
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algorithm. The results should be the same within
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numerical noise.
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fpol if .true. calculate dynamic polarizabilities .false.
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( experimantal stage, see example33 for calculation
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of methane )
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lnscf If .TRUE. the run makes first a nscf calculation .false.
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ldisp If .TRUE. the run calculates phonons for a grid of .false.
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q-points specified by nq1, nq2, nq3 - for direct
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calculation of the entire phonon dispersion.
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The pw.x data file should not be produced using
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"calculation='phonon'" in this case
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nq1,nq2,nq3 parameters of the Monkhorst-Pack grid (no offset) used 0,0,0
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when ldisp=.true. Same meaning as for nk1, nk2, nk3
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in the input of pw.x
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nrapp choose the subset of irreducible representations (irreps)
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for which the linear response calculation is performed:
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"nrapp" irreps, specified in input (see below) are used.
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Default: nrapp=0, i.e. use all irreps . nrapp must be <= 3*nat
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Do not specify "nat_todo" together with "nrapp"
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maxirr perform calculations only up to the first "maxirr" irreps.
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Default: maxirr=0, i.e. use all irreps. maxirr must be <= 3*nat
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Do not specify "nat_todo" or "nrapp" together with "maxirr"
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nat_todo choose the subset of atoms to be used in the linear response
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calculation: "nat_todo" atoms, specified in input (see below)
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are displaced. Default: nat_todo=0, i.e. displace all atoms
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Do not specify "nrapp" together with "nat_todo"
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End of namelist "inputph"
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card 2 xq(3) the phonon wavevector; must be equal to the one used
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in the non-selfconsistent calculation (not read if
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ldisp is true).
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card 3 list(na), na = 1, nrapp
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contains the list of indices of irreps used in the
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calculation if "nrapp" is specified
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OR:
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card 3 atomo(na), na = 1, nat_todo
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contains the list of indices of atoms used in the
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calculation if "nat_todo" is specified
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