------------------------------------------------------------------------ INPUT FILE DESCRIPTION Program: ph.x / PWscf / Quantum Espresso ------------------------------------------------------------------------ Input data format: { } = optional, [ ] = it depends, # = comment Structure of the input data: =============================================================================== title_line &INPUTPH ... / xq(1) xq(2) xq(3) [ irrep(1) irrep(2) ... irrep(nrapp) ] # if "nrapp" was specified [ atom(1) atom(2) ... atom(nat_todo) ] # if "nat_todo" was specified ======================================================================== Line of input: title_ph DESCRIPTION OF ITEMS: +-------------------------------------------------------------------- Variable: title_ph Type: CHARACTER Description: Title of the job, i.e., a line that is reprinted on output. +-------------------------------------------------------------------- ===End of line-of-input================================================= ======================================================================== NAMELIST: &INPUTPH +-------------------------------------------------------------------- Variable: amass(i), i=1,ntyp Type: REAL Default: 0.0 Description: Atomic mass [amu] of each atomic type. If not specified, masses are read from data file +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: outdir Type: CHARACTER Default: './' Description: Scratch directory. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: prefix Type: CHARACTER Default: 'pwscf' Description: Prepended to input/output filenames; must be the same used in the calculation of unperturbed system. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: niter_ph Type: INTEGER Default: 50 Description: Maximum number of iterations in a scf step. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: tr2_ph Type: REAL Description: Threshold for selfconsistency. Default: 1e-10 +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: alpha_mix(niter) Type: REAL Default: alpha_mix(1)=0.7 Description: Mixing factor (for each iteration) for updating the scf potential: vnew(in) = alpha_mix*vold(out) + (1-alpha_mix)*vold(in) +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: nmix_ph Type: INTEGER Description: Number of iterations used in potential mixing. Default: 4 +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: iverbosity Type: INTEGER Default: 0 Description: 0 = short output 1 = verbose output +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: reduce_io Type: LOGICAL Description: Reduce I/O to the strict minimum. Default: .false. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: max_seconds Type: REAL Description: Maximum allowed run time before the job stops smoothly. Default: 1.d7 +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: fildyn Type: CHARACTER Description: File where the dynamical matrix is written. Default: 'matdyn' +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: fildrho Type: CHARACTER Description: File where the charge density responses are written. Default: ' ' +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: fildvscf Type: CHARACTER Description: File where the the potential variation is written (for later use in electron-phonon calculation). Default: ' ' +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: epsil Type: LOGICAL Default: .false. Description: If .true. in a q=0 calculation for a non metal the macroscopic dielectric constant of the system is computed. Do not set epsil to .true. if you have a metallic system or q/=0: the code will complain and stop +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: lrpa Type: LOGICAL Description: If .true. the dielectric constant is calculated at the RPA level with DV_xc=0. Default: .false. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: lnoloc Type: LOGICAL Description: If .true. the dielectric constant is calculated without local fields, i.e. by setting DV_H=0 and DV_xc=0. Default: .false. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: trans Type: LOGICAL Description: if .true. the phonons are computed if trans .and. epsil effective charges are calculated Default: .true. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: lraman Type: LOGICAL Default: .false. Description: if .true. calculate nonresonant Raman coefficients using second-order response as in: M. Lazzeri and F. Mauri, Phys. Rev. Lett. 90, 036401 (2003) +-------------------------------------------------------------------- ///--- OPTIONAL VARIABLES FOR RAMAN: +-------------------------------------------------------------------- Variable: eth_rps Type: REAL Description: threshold for calculation of Pc R |psi> Default: 1.0d-9 +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: eth_ns Type: REAL Description: threshold for non-scf wavefunction calculation Default: 1.0e-12 +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: dek Type: REAL Description: delta_xk used for wavefunction derivation wrt k Default: 1.0e-3 +-------------------------------------------------------------------- \\\--- +-------------------------------------------------------------------- Variable: recover Type: LOGICAL Description: if .true. restart from an interrupted run Default: .false. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: elph Type: LOGICAL Default: .false. Description: if .true. electron-phonon lambda coeffs are computed For metals only, requires gaussian smearing. If elph .and. trans, the lambdas are calculated in the same run, using the same k-point grid for phonons and lambdas If elph.and..not.trans, the lambdas are calculated using previously saved DeltaVscf in fildvscf, previously saved dynamical matrix, and the present punch file. This allows the use of a different (larger) k-point grid. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: zue Type: LOGICAL Description: if .true. in a q=0 calculation for a non metal the effective charges are computed from the phonon density responses. Note that if trans.and.epsil effective charges are calculated using a different algorithm. The results should be the same within numerical noise. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: elop Type: LOGICAL Default: .false. Description: if true calculate electro-optic tensor +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: fpol Type: LOGICAL Default: .false. Description: if .true. calculate dynamic polarizabilities ( experimantal stage, see example33 for calculation of methane ) +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: lnscf Type: LOGICAL Description: If .TRUE. the run makes first a nscf calculation. Default: .false. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: ldisp Type: LOGICAL Default: .false. Description: If .TRUE. the run calculates phonons for a grid of q-points specified by nq1, nq2, nq3 - for direct calculation of the entire phonon dispersion. The pw.x data file should not be produced using "calculation='phonon'" in this case. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variables: nq1, nq2, nq3 Type: INTEGER Default: 0 Description: Parameters of the Monkhorst-Pack grid (no offset) used when ldisp=.true. Same meaning as for nk1, nk2, nk3 in the input of pw.x. +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variables: iq1, iq2, iq3 Type: INTEGER Description: These go together with nq1, nq2, nq3 and allow to choose just one point out of the Monkhorst-Pack grid with ldisp=.true. Note the the actual point chosen is something like (iq1-1)/nq1, (iq2-1)/nq2, (iq3-1)/nq3 (so, check the output for what you get). Also make sure that PW left *.wfc files behind (no 'phonon' is needed though). +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: nrapp Type: INTEGER Default: 0, i.e. use all irreps Description: Choose the subset of irreducible representations (irreps) for which the linear response calculation is performed: "nrapp" irreps, specified in input (see below) are used. IMPORTANT: * nrapp must be <= 3*nat * do not specify "nat_todo" together with "nrapp" +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: maxirr Type: INTEGER Default: 0, i.e. use all irreps Description: Perform calculations only up to the first "maxirr" irreps. IMPORTANT: * maxirr must be <= 3*nat * do not specify "nat_todo" or "nrapp" together with "maxirr" +-------------------------------------------------------------------- +-------------------------------------------------------------------- Variable: nat_todo Type: INTEGER Default: 0, i.e. displace all atoms Description: Choose the subset of atoms to be used in the linear response calculation: "nat_todo" atoms, specified in input (see below) are displaced. IMPORTANT: * nat_todo <= nat * do not specify "nrapp" together with "nat_todo" +-------------------------------------------------------------------- ===END OF NAMELIST====================================================== ///--- ======================================================================== Line of input: xq(1) xq(2) xq(3) DESCRIPTION OF ITEMS: +-------------------------------------------------------------------- Variables: xq(1) xq(2) xq(3) Type: REAL Description: The phonon wavevector; must be equal to the one used in the non-selfconsistent calculation (not read if ldisp is true). +-------------------------------------------------------------------- ===End of line-of-input================================================= \\\--- ________________________________________________________________________ * IF nrapp was specified : ======================================================================== Line of input: irrep(1) irrep(2) ... irrep(nrapp) DESCRIPTION OF ITEMS: +-------------------------------------------------------------------- Variables: irrep(1) irrep(2) ... irrep(nrapp) Type: INTEGER Description: The list of indices of irreps used in the calculation if "nrapp" is specified. +-------------------------------------------------------------------- ===End of line-of-input================================================= * ELSE IF nat_todo was specified : ======================================================================== Line of input: atom(1) atom(2) ... atom(nat_todo) DESCRIPTION OF ITEMS: +-------------------------------------------------------------------- Variables: atom(1) atom(2) ... atom(nat_todo) Type: INTEGER Description: Contains the list of indices of atoms used in the calculation if "nat_todo" is specified. +-------------------------------------------------------------------- ===End of line-of-input================================================= ENDIF ________________________________________________________________________