Description:

Libint library is used to evaluate the traditional (electron repulsion) and
certain novel two-body matrix elements (integrals) over Cartesian Gaussian
functions used in modern atomic and molecular theory. The idea of the library
is to let computer write optimized code for computing such integrals. There
are two primary advantages to this: much less human effort is required to
write code for computing new integrals, and code can be optimized specifically
for a particular computer architecture (e.g., vector processor).

Libint has been utilized to implement methods such as Hartree-Fock (HF) and
Kohn-Sham density functional theory (KS DFT), second-order Moller-Plesset
perturbation theory (MP2), coupled cluster singles and doubles (CCSD)
method, as well as explicitly correlated R12 methods.