where in the first term k runs on the doubly occupied MOs in the ground state configuration, while the second term accounts for the singly occupied MO (SOMO). c kµ are the expansion coefficients of the k-th MO on the AOs (see SI, Section S1, Eqs. S1 and S2). The Fock operator above is addressed self-consistently through the variational principle. Typically, around 40 HF iterations are required to achieve convergence on the density matrix elements.