/*
* Function: Normalize
*
* The program compute the normalization of the GTO.
*
* Parameter:
*
* const GTO *g contain the angular momentum(l, m, n).
* const GTO_PARTIAL *gp contain the exponent and the contract
* coefficient
*/
inline double Normalize(const GTO *g, const GTO_PARTIAL *gp)
{
double alpha = gp->alpha;
int l = g->l;
int m = g->m;
int n = g->n;
return gp->coeff * pow(2*alpha/M_PI, 0.75) * sqrt(pow(4*alpha, l + m + n)/
(factorial_2(2*l-1) * factorial_2(2*m-1) * factorial_2(2*n-1)));
}
double I_xyz(int l1, double pax, int l2, double pbx, double gamma, int flags)
{
// 《量子化学》中册 P63 (10.6.8) (10.6.9) (10.6.10)
int i;
double sum = 0;
// BUG 2i
for (i = 0; i < floor((l1 + l2) * 0.5) + 1; i++) {
sum += factorial_2(2*i - 1) / gsl_pow_int(2 * gamma, i) * \
fi_l_ll_pax_pbx(2*i, l1, l2, pax, pbx, flags);
}
return sum;
}