DFT calculations were performed using the Gaussian16 (Rev. C.01) suite of software. All calculations were performed using the B3LYP functional and the 6-31G(d,p) basis set for non-metal atoms and the SBKJC VDZ ECP basis set for the Ir atom, using the conductor-like polarizable continuum model (CPCM) for acetonitrile solution. Geometry optimizations of the triplet excited state were performed using the optimized singlet structures as starting points. Vibrational frequency calculations were performed on all optimised structures to ensure that the optimized geometries represented the local minima. Excited-state energies were calculated using the TD-DFT formalism. Calculations were submitted and processed using the Digichem software package (version 6), which incorporates a number of publicly available software libraries, including: cclib for parsing of result files, VMD /Tachyon 34 for 3D rendering, Matplotlib for drawing of graphs, Open Babel 36 /Pybel 37 for file interconversion and PySOC 38 for the calculation of spin-orbit coupling. Chemissian v4.80 was used to calculate and visualize the fractional contributions of various groups to each molecular orbital. Calculated structures and Kohn-Sham orbitals were visualized with Gaussview v5.0.