Explicitly correlated Gaussians for high-precision variational calculations of S^{e}, P^{e}, and D^{e} states of quantum systems: An efficient algorithm.

In this work we consider an efficient algorithm for variational calculations of quantum few-particle systems in S, P, and D states of the even parity using all-particle explicitly correlated Gaussian (ECG) basis sets. We primarily focus on the description of states where the dominant configuration contains either two particles in p states or a single particle in a d state (all other particles are in s states). The basis functions we consider are products of spherically symmetric ECGs and bipolar harmonics.