  Analytical forces have been derived in the Lagrangian framework for several
random phase approximation (RPA) correlated total energy methods based on the
range separated hybrid (RSH) approach, which combines a short-range density
functional approximation for the short-range exchange-correlation energy with a
Hartree-Fock-type long-range exchange and RPA long-range correlation. The RPA
correlation energy has been expressed as a ring coupled cluster doubles (rCCD)
theory. The resulting analytical gradients have been implemented and tested for
geometry optimization of simple molecules and intermolecular charge transfer
complexes, where intermolecular interactions are expected to have a
non-negligible effect even on geometrical parameters of the monomers.
