A spin‐dependent unitary group approach to many‐electron systems

Abstract
In this article we derive a segment‐level formula for the matrix elements of the U(2n) generators in a basis symmetry adapted to the subgroup U(n) × U(2) (i.e., spin‐orbit basis), for the representations appropriate to many‐electron systems. This enables the direct evaluation of the matrix elements of spin‐dependent Hamiltonians.