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Physical Constants

Physical constants in Psi4
Label Value Description
psi_h 6.62606896E-34 The Planck constant (Js)
psi_c 2.99792458E8 Speed of light (ms$^{-1}$)
psi_kb 1.3806504E-23 The Boltzmann constant (JK$^{-1}$)
psi_R 8.314472 Universal gas constant (JK$^{-1}$mol$^{-1}$)
psi_bohr2angstroms 0.52917720859 Bohr to Angstroms conversion factor
psi_bohr2m 0.52917720859E-10 Bohr to meters conversion factor
psi_bohr2cm 0.52917720859E-8 Bohr to centimeters conversion factor
psi_amu2g 1.660538782E-24 Atomic mass units to grams conversion factor
psi_amu2kg 1.660538782E-27 Atomic mass units to kg conversion factor
psi_au2amu 5.485799097E-4 Atomic units (m$@@e$) to atomic mass units conversion factor
psi_hartree2J 4.359744E-18 Hartree to joule conversion factor
psi_hartree2aJ 4.359744 Hartree to attojoule (10$^{-18}$J) conversion factor
psi_cal2J 4.184 Calorie to joule conversion factor
psi_dipmom_au2si 8.47835281E-30 Atomic units to SI units (Cm) conversion factor for dipoles
psi_dipmom_au2debye 2.54174623 Atomic units to Debye conversion factor for dipoles
psi_dipmom_debye2si 3.335640952E-30 Debye to SI units (Cm) conversion factor for dipoles
psi_c_au 137.035999679 Speed of light in atomic units
psi_hartree2ev 27.21138 Hartree to eV conversion factor
psi_hartree2wavenumbers 219474.6 Hartree to cm$^{-1}$ conversion factor
psi_hartree2kcalmol 627.5095 Hartree to kcal mol$^{-1}$ conversion factor
psi_hartree2kJmol 2625.500 Hartree to kilojoule mol$^{-1}$ conversion factor
psi_hartree2MHz 6.579684E9 Hartree to MHz conversion factor
psi_kcalmol2wavenumbers 349.7551 kcal mol$^{-1}$ to cm$^{-1}$ conversion factor
psi_e0 8.854187817E-12 Vacuum permittivity (Fm$^{-1}$)
psi_na 6.02214179E23 Avagadro’s number
psi_me 9.10938215E-31 Electron rest mass (in kg)