where â † p creates an α-spin electron in orbital ψ p and âq annihilates a β-spin electron in orbital ψ q . Previous work by Li and Liu uses a different working equation as a TEOM as compared to that used in SA-SF-CIS and SA-SF-DFT, and that equation generates spurious solutions due to the presence of redundant terms in the excitation space. The working equation used by Zhang and Herbert for SA-SF-TDDFT avoids this problem. The overall tensor operator can be written as