SEARCH Articles Figures Tables Basis-Set Expansions of Relativistic Electronic Wave Functions Cluster expansion methods wave-function Expansion function Expansion in a basis of orbital wave functions Expansion of the Wave Function Expansion wave Functional expansion Variational calculations wave function expansion, correlation Wave function double perturbation expansion Wave function expansions coefficient Wave function expansions radial orbitals Wave function expansions transition matrix elements Wave functions exact, expansion Wave-function Cluster Expansion