mirror of
https://gitlab.com/scemama/QCaml.git
synced 2024-11-18 20:12:26 +01:00
45 lines
1.6 KiB
OCaml
45 lines
1.6 KiB
OCaml
|
|
|
|
(* | ~epsilon~ | Value below which a float is considered null. Default is \epsilon = 2.10^{-15} |
|
|
* | ~integrals_cutoff~ | Cutoff value for integrals. Default is \epsilon | *)
|
|
|
|
|
|
(* [[file:~/QCaml/common/constants.org::*Thresholds][Thresholds:2]] *)
|
|
let epsilon = 2.e-15
|
|
let integrals_cutoff = epsilon
|
|
(* Thresholds:2 ends here *)
|
|
|
|
|
|
|
|
(* | ~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~ | $2 / \sqrt{\pi}$ | *)
|
|
|
|
|
|
(* [[file:~/QCaml/common/constants.org::*Mathematical%20constants][Mathematical constants:2]] *)
|
|
let pi = acos (-1.)
|
|
let two_pi = 2. *. pi
|
|
let sq_pi = sqrt pi
|
|
let sq_pi_over_two = sq_pi *. 0.5
|
|
let pi_inv = 1. /. pi
|
|
let two_over_sq_pi = 2. /. sq_pi
|
|
(* Mathematical constants:2 ends here *)
|
|
|
|
|
|
|
|
(* | ~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~ | *)
|
|
|
|
|
|
(* [[file:~/QCaml/common/constants.org::*Physical%20constants][Physical constants:2]] *)
|
|
let a0 = 0.529_177_210_67
|
|
let a0_inv = 1. /. a0
|
|
let ha_to_ev = 27.211_386_02
|
|
let ev_to_ha = 1. /. ha_to_ev
|
|
(* Physical constants:2 ends here *)
|