On incorporation of atomic correlation in transition-metal molecular calculations: NiH

The atomic correlation terms necessary to lead to anaccurate 4s²3d⁸-4s^t 3d⁹ separation for the Ni atom have been incorporated into all-electron MC SCF/Cl calculations for the X² Δ state of NiH. The calculated potential curve properties are significantly improved compared to calculations which dissociate to Hartree-Fock atoms.