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.
DOSIN, DOSEND,
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), (0.0,0.0,0.0)
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, FREQ.cm	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.cm, 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)