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45 lines
1.6 KiB
OCaml
45 lines
1.6 KiB
OCaml
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(* | ~epsilon~ | Value below which a float is considered null. Default is \epsilon = 2.10^{-15} |
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* | ~integrals_cutoff~ | Cutoff value for integrals. Default is \epsilon | *)
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(* [[file:~/QCaml/common/constants.org::*Thresholds][Thresholds:2]] *)
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let epsilon = 2.e-15
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let integrals_cutoff = epsilon
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(* Thresholds:2 ends here *)
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(* | ~pi~ | $\pi = 3.141~592~653~589~793~12$ |
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* | ~two_pi~ | $2 \pi$ |
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* | ~sq_pi~ | $\sqrt{\pi}$ |
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* | ~sq_pi_over_two~ | $\sqrt{\pi} / 2$ |
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* | ~pi_inv~ | $1 / \pi$ |
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* | ~two_over_sq_pi~ | $2 / \sqrt{\pi}$ | *)
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(* [[file:~/QCaml/common/constants.org::*Mathematical constants][Mathematical constants:2]] *)
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let pi = acos (-1.)
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let two_pi = 2. *. pi
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let sq_pi = sqrt pi
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let sq_pi_over_two = sq_pi *. 0.5
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let pi_inv = 1. /. pi
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let two_over_sq_pi = 2. /. sq_pi
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(* Mathematical constants:2 ends here *)
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(* | ~a0~ | Bohr's radius : $a_0 = 0.529~177~210~67(23)$ angstrom |
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* | ~a0_inv~ | $1 / a_0$ |
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* | ~ha_to_ev~ | Hartree to eV conversion factor : $27.211~386~02(17)$ |
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* | ~ev_to_ha~ | eV to Hartree conversion factor : 1 / ~ha_to_ev~ | *)
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(* [[file:~/QCaml/common/constants.org::*Physical constants][Physical constants:2]] *)
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let a0 = 0.529_177_210_67
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let a0_inv = 1. /. a0
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let ha_to_ev = 27.211_386_02
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let ev_to_ha = 1. /. ha_to_ev
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(* Physical constants:2 ends here *)
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