PWCOND input parameters

outdir: CHARACTER
Temporary directory (same as in PWscf).

ikind: INTEGER
Specifies the type of calculation:
ikind=0 – complex band structure (CBS) calculation;
ikind=1 – conductance calculation for a system with IDENTICAL left and right leads;
ikind=2 – conductance calculation for a system with DIFFERENT left and right leads.
Default: 0.

prefixt: CHAR
Prefix for the file (as in PWscf) containing all the regions (left lead + scatt. reg. + right lead).
Default: none.

prefixl: CHAR
Prefix for the file containing only the left lead.
Default: none.

prefixs: CHAR
Prefix for the file containing only the scattering region.
Default: none.

prefixr: CHAR
Prefix for the file containing only the right lead.
Default: none.

bdl: REAL
Right boundary of the left lead (left one is at 0).
Default: the end of the cell.

bds: REAL
Right boundary of the scattering region (left one is at 0 if prefixs is used and at bdl if prefixt is used).
Default: the end of the cell.

bdr: REAL
Right boundary of the right lead (left one is at 0 if prefixr is used and at bds if prefixt is used).
Default: the end of the cell.

iofspin: INTEGER
Spin index (in spin-polarised collinear case).
Default: 1.

ewind: REAL
Energy window for reducing 2D plane wave basis set (in the transverse XY plane).
The larger ewind the higher accuracy.
Default: 1 Ry.

epsproj: REAL
Threshold for reduction of the 2D basis set (see also ewind).
The smaller epsproj the higher accuracy.
Default: 0.001.

nz1: INTEGER
The number of subslabs in the slab for numerical calculation of various integrals.
The bigger nz1 the higher accuracy.
Default: 11.

band_file: CHARACTER
The file where complex band structure is written.
Default: none (no output).

tran_file: CHARACTER
The file where the transmission function is written.
Default: none (no output).

energy0: REAL
The initial energy, measured in eV from the Fermi energy.
Default: 0.0 (the Fermi energy).

energy0: REAL
The step in energy. If denergy=0.0 the energy is read from the list, see below.
Default: 0.0.

lorb: LOGICAL
If .true. the scattering states (the XY average vs. Z) are plotted on general file.
Default: .false.

lorb3d: LOGICAL
If .true. the full 3d plot of the scattering states is written on files wfc_*.
Default: .false.

lcharge: LOGICAL
If .true. the charge density (integrated in XY plane vs. Z) calculated on scattering states is written on general file.
Default: .false.

tran_prefix: CHARACTER
If specified, partial results of transmission calculation (ikind > 0) are saved in outdir/tran_prefix.cond_save.
Default: none.

recover: LOGICAL
Restarts a previously interrupted transmission calculation (only if tran_prefix was specified).
It also collects the partial results if the calculation was split by using (start_e, last_e) and/or (start_k, last_k).
Default: .false.

max_seconds: REAL
The time (in sec.) after which the job stops. It can be enabled only if tran_prefix is specified.
Default: 1.d+7 seconds, i.e. no time limit.

start_e: INTEGER
If specified, the energy index at which the calculation starts.
Default: 0 (the calculation starts from initial energy).

last_e: INTEGER
If specified, the energy index at which the calculation stops.
Default: 0 (the calculation stops at the last energy).

start_k: INTEGER
If specified, the k_perp at which the calculation starts.
NOTE: To recover the full transmission, integrated over 2D Brillouin Zone, perform the partial runs specifying a value for tran_prefix (the restart directory), then put all the partial transmission files ‘transmission_k#_e#’ inside a restart directory and run pwcond.x with recover=.true. (without specifying start_k and last_k).
Default: 0 (the calculation starts with the first k).

last_k: INTEGER
If specified, the k_perp at which the calculation stops.
Default: 0 (the calculation stops at the last k).

lwrite_loc: LOGICAL
If .true. save 2D eigenvalue problem results in the file fil_loc.
Default: .false.

lread_loc: LOGICAL
If .true. read 2D eigenvalue problem results from the file fil_loc.
Default: .false.

fil_loc: CHARACTER
The file where the 2D eigenvalue problem results are stored.
Default: none

lwrite_cond: LOGICAL
If .true. save the data necessary for PWCOND in save_file.
Default: .false.

lread_cond: LOGICAL
If .true. read the data necessary for PWCOND from save_file.
Default: .false.

save_file: CHARACTER
The file where the data necessary for PWCOND are stored.
Default: none

orbj_in: INTEGER
The code gives in output scalar products of scattering states with projector functions from orbj_in to orbj_fin.
Default: 0 (no output).

orbj_fin: INTEGER
See orbj_in.
Default: 0 (no output).

llocal: LOGICAL
If .true. the calculations are done with only local part of pseudopotentials.
Default: .false.

ecut2d: REAL
The energy cut-off for expanding the wave functions over 2D plane waves in the XY plane.
Default: 0 (the cut-off from previous PW calculations is used).

delgep: REAL
A small number added for stability reason to matrices at the step of solving generalized eigenvalue problem (finding the complex band structure of the leads).
Default: 5.d-10

cutplot: REAL
Cut-off on imaginary part of complex k vectors which will be written in band_file if it was specified.
NOTE: no effect on calculations.
Default: 2.0