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Input variables and Input/Output files

A full list of input variables is reported in Table 1, and a list of the input/output files needed/generated by PHON is reported in Table 2

Table 1: Input variables
Input variable Meaning Variable type Default
NTYPES Number of atomic types Integer No default
MASS Mass of atoms Real*NTYPES 1.0
LSUPER Generate supercell Logical .T.
NDIM Supercell dimensions Integer*3 (1,1,1)
LFREE Thermodynamic properties Logical .F.
TEMPERATURE Temperature Real No default
PTEMP Temperature increment, number of increments Real*2 (0.0, 1.0)
LFORCEOUT Writes force constant matrix file Logical .F.
LSYMM Symmetrises force constant matrix Logical .T.
SYMPREC Precision threshold Real 1d-5
DXSTART Initial displacement Real*3 (1.0, 0.0, 0.0)
DISP One over size of displacement (in Å$^{-1}$) Integer 25 (0.04 Å)
LCENTRAL For central differences Logical .F. (Forward differences)
QA, QB, QC Number of divisions for q-points grid Integers No defaults
LGAMMA q-points grid through $\Gamma $ Logical .F.
DOSSTEP Density of states parameters Reals 0.0, 25.0, 0.1 (THz)
DOSSMEAR Width of Gaussian convoluted with DOS Real 0.02 (THz)
USETHIS Partial density of states Logic*NTYPES .T. (total DOS)
ND Number of q-points in dispersion segments Integer 0
QI, QF Initial and final points for dispersion segments Real*3 (0.0,, (0.0,0.0,0.0)
LRECIP q-points in reciprocal lattice coordinates Logical .T.
NTI Imposes translational invariance Integer 1 (no TI imposed)
IPRINT Controls verbosity of output Integer 0 (little output)
LEIGEN Graphical representation of vibrations Logical .F. (no graphics)
NAME? Name of atoms in the primitive cell Character*NTYPES H
EIGSIZE Amplitude of vibrations Real 1.0
NCYCLESEIG Number of vibration cycles Integer 2

Table 2: Input/Output files
File name Input/Output Description of data
INPHON Input Input variables
POSCAR Input Supercell
FORCES Input Forces on all atoms (eV/Å), for each displacement
QPOINTS Input/Output q-points for thermodynamics
DISP Output Suggestions for displacements
SPOSCAR Output File containing supercell
FREQ, Output (if natoms $<=$16) Phonon dispersions (THz and cm$^{-1}$)
FREQi, i=1,natoms/16 Output (if natoms $>$ 16) Phonon dispersions in groups of 48 (THz)
DOS,, DOS.meV Output Density of states (THz, cm$^{-1}$, meV)
THERMO Output Thermodynamic properties
HARMONIC Output Force constant matrix
EIGEN.axsf Output Eigenvectors (for representation with XCrySDen)
MODE???.axsf Output Phonon vibrations (for representation with XCrySDen)

next up previous
Next: Test case Up: Description of the program Previous: Graphical representation of phonons
Dario Alfe` 2012-02-20