Here, we seek to explore the relationship between the molecular geometries and electronic structure in the bare and meso-triphenyl copper corrole using multireference methods. XMS-CASPT2 molecular geometries for the S 0 , S 1 , and T 0 states are reported for the unsubstituted copper corrole and the meso-substituted 5,10,15-triphenyl copper corrole, followed by an electronic structure study with larger complete and restricted active space choices. XMS-CASPT2 enthalpy difference between the S 0 and T 0 states is reported. How the electronic structure changes along a slice of the potential energy surface (PES), between the XMS-CASPT2 (or DFT) S 0 and T 0 minimum energy structures, is demonstrated. The spin-state energetics are explored along the PES and the oxidation state of copper is assigned at the respective minima for the two corrole complexes. We seek to understand if the differences between the two previous studies are a result of the molecular geometries, active space choices, or a combination of the two factors.