Code: hydrogen gauss

Code hydrogengauss.f90 1 (or hydrogen gauss.c2) solves the secular prob-lem for the hydrogen atom using two different non-orthonormal basis sets:

1. a Gaussian, “S-wave” basis set:bi(r) =e−αir2;(5.24)

2. a Gaussian “P-wave” basis set, existing in three different choices, corresponding to the different values mof the projection of the angular mo-mentumLz:bi(r) =xe−αir2, bi(r) =ye−αir2, bi(r) =ze−αir2(5.25)(actually only the third choice corresponds to a well-defined valuem= 0).