Second-order correlation energy of the argon atom using basis sets of Gaussian-type functions

The second-order correlation energy of the ground state of the argon atoms is calculated using basis sets of Gaussian-type functions. It is demonstrated that accurate second-order correlation energies can be obtained by employing systematic sequences of even-tempered basis sets of Gaussian-type functions. The pair correlation energies are compared with those obtained by Jankowski et al. (1979) using basis sets of exponential-type functions.