Flexible d basis sets for Sc through Cu

A prescription is presented and implemented for Sc through Cu that leads to practical-sized Gaussian d basis sets capable of accurate descriptions of the s^md^n-m states of the atom. Optimized Gaussian basis sets containing four, five, and six primitives are given along with recommended double zeta, double zeta, and triple zeta contraction schemes, respectively. It is suggested that these basis sets be used for calculations on large, medium, and small transition metal complexes, respectively.