1# Copyright (C) 2011 Atsushi Togo
2# All rights reserved.
3#
4# This file is part of phonopy.
5#
6# Redistribution and use in source and binary forms, with or without
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13# * Redistributions in binary form must reproduce the above copyright
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22# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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34
35from math import pi, sqrt
36
37kb_J = 1.3806504e-23  # [J/K]
38PlanckConstant = 4.13566733e-15  # [eV s]
39Hbar = PlanckConstant/(2*pi)  # [eV s]
40Avogadro = 6.02214179e23
41SpeedOfLight = 299792458  # [m/s]
42AMU = 1.6605402e-27  # [kg]
43Newton = 1.0         # [kg m / s^2]
44Joule = 1.0          # [kg m^2 / s^2]
45EV = 1.60217733e-19  # [J]
46Angstrom = 1.0e-10   # [m]
47THz = 1.0e12         # [/s]
48Mu0 = 4.0e-7 * pi    # [Hartree/m]
49Epsilon0 = 1.0 / Mu0 / SpeedOfLight**2  # [C^2 / N m^2]
50Me = 9.10938215e-31
51
52Bohr = 4e10 * pi * Epsilon0 * Hbar**2 / Me   # Bohr radius [A] 0.5291772
53Hartree = Me * EV / 16 / pi**2 / Epsilon0**2 / Hbar**2  # Hartree [eV] 27.211398
54Rydberg = Hartree / 2  # Rydberg [eV] 13.6056991
55
56THzToEv = PlanckConstant * 1e12  # [eV]
57Kb = kb_J / EV   # [eV/K] 8.6173383e-05
58THzToCm = 1.0e12 / (SpeedOfLight * 100)  # [cm^-1] 33.356410
59CmToEv = THzToEv / THzToCm  # [eV] 1.2398419e-4
60VaspToEv = sqrt(EV/AMU)/Angstrom/(2*pi)*PlanckConstant  # [eV] 6.46541380e-2
61VaspToTHz = sqrt(EV/AMU)/Angstrom/(2*pi)/1e12  # [THz] 15.633302
62VaspToCm = VaspToTHz * THzToCm  # [cm^-1] 521.47083
63EvTokJmol = EV / 1000 * Avogadro  # [kJ/mol] 96.4853910
64Wien2kToTHz = sqrt(Rydberg/1000*EV/AMU)/(Bohr*1e-10)/(2*pi)/1e12  # [THz] 3.44595837
65AbinitToTHz = sqrt(EV/(AMU*Bohr))/Angstrom/(2*pi)/1e12  # [THz] 21.49068
66PwscfToTHz = sqrt(Rydberg*EV/AMU)/(Bohr*1e-10)/(2*pi)/1e12  # [THz] 108.97077
67ElkToTHz = sqrt(Hartree*EV/AMU)/(Bohr*1e-10)/(2*pi)/1e12  # [THz] 154.10794
68SiestaToTHz = sqrt(EV/(AMU*Bohr))/Angstrom/(2*pi)/1e12  # [THz] 21.49068
69CP2KToTHz = sqrt(Hartree*EV/(AMU*Bohr))/Angstrom/(2*pi)/1e12  # CP2K uses a.u. for forces but Angstrom for distances
70CrystalToTHz = VaspToTHz
71CastepToTHz = VaspToTHz
72DftbpToTHz = sqrt(Hartree*EV/AMU)/(Bohr*1e-10)/(2*pi)/1e12 # [THz] 154.10794344
73dftbpToBohr = 0.188972598857892E+01
74TurbomoleToTHz = ElkToTHz # Turbomole uses atomic units (Hartree/Bohr)
75EVAngstromToGPa = EV * 1e21
76FleurToTHz = ElkToTHz # Fleur uses atomic units (Hartree/Bohr)
77