Mapping the d-d Excited-State Manifolds of Transition Metal beta-Diiminato-Imido Complexes. Comparison of Density Functional Theory and CASPT2 Energetics
Trigonal-planar, middle transition metal diiminato-imido complexes do not exhibit high-spin states, as might be naively expected on the basis of their low coordination numbers. Instead, the known Fe(III), Co(III), and Ni(III) complexes exhibit S = (3)/(2), S = 0, and S = (1)/(2), ground states, respectively. Kohn-Sham DFT calculations have provided a basic molecular orbital picture of these compou