Dimeric complexes composed of d8 square planar metal centers and rigid bridg- ing ligands provide model systems to understand the interplay between attractive dispersion forces and steric strain, in order to assist the development reliable meth- ods to model metal dimer complexes more broadly. [Ir2(dimen)4]2+ (dimen = para- diisocyanomenthane) presents a unique case study for such phenomena, as distortions of the optimal structure of a ligand with limited conformational flexibility counteracts the attractive dispersive forces from the metal and ligand to yield a complex with two ground state deformational isomers. Here, we use ultrafast X-ray solution scattering (XSS) and optical transient absorption spectroscopy (OTAS) to reveal the nature of the equilibrium distribution and the exchange rate between the deformational isomers. The two ground state isomers have spectrally distinct electronic excitations that enable the selective excitation of one isomer or the other using a femtosecond duration pulse of visible light. We then track the dynamics of the non-equilibrium depletion of the electronic ground state population – often termed the ground state hole – with ultra- fast XSS and OTAS, revealing a restoration of the ground state equilibrium in 2.3 ps. This experimental study provides a critical test of various density functional approx- imations in the description of bridged d8-d8 metal complexes. Our study shows that reproduction of the primary experimental observations requires a hybrid functional, which includes exact exchange, while also accounting for dispersion interactions.