The geometries of the 18 new complexes and of VCl 3 (ddpd)were optimized in their triplet ground states at the unrestricted density functional theory (DFT) level of theory using the B3LYP functional 2,3 and ZORA-def2-SVP basis sets. Calculations were performed using the ORCA4.2.1 program package 5 including the D3 dispersion correction using Becke-Johnson damping (D3BJ). Scalar relativistic effects were taken into account with the zeroth-order regular approximation 7 (ZORA). Solvent effects for acetonitrile were modeled using the conductor polarizable continuum model (C-PCM). For the self-consistent-field (SCF) calculations, the resolution-of-identity approximation (RIJCOSX), 9 def2/J auxiliary basis functions, 10 tight SCF convergence criteria (TightSCF), and the Grid4 integration grid were used.