QCaml/common/constants.org

2.4 KiB

Constants

All constants used in the program.

Thresholds

val epsilon          : float
val integrals_cutoff : float
epsilon Value below which a float is considered null. Default is ε = 2.10-15
integrals_cutoff Cutoff value for integrals. Default is ε

Mathematical constants

val pi             : float
val two_pi         : float
val sq_pi          : float
val sq_pi_over_two : float
val pi_inv         : float
val two_over_sq_pi : float
pi $\pi = 3.141~592~653~589~793~12$
two_pi $2 \pi$
sq_pi $\sqrt{\pi}$
sq_pi_over_two $\sqrt{\pi} / 2$
pi_inv $1 / \pi$
two_over_sq_pi $2 / \sqrt{\pi}$

Physical constants

val a0       : float
val a0_inv   : float
val ha_to_ev : float
val ev_to_ha : float
a0 Bohr's radius : $a_0 = 0.529~177~210~67(23)$ angstrom
a0_inv $1 / a_0$
ha_to_ev Hartree to eV conversion factor : $27.211~386~02(17)$
ev_to_ha eV to Hartree conversion factor : 1 / ha_to_ev