DFT-optimized structures of the terminal (a, b) and bridging (c, d) hydride isomeric species including their d- (a and c) and p- (b and d) flippamer alternatives on the Me2pdt2− bridge conformation. Notations of the species are provided ([td-H1]+, [tp-H1]+, [μd-H1]+, [μp-H1]+). Important atomic labels are provided in (a and c). The Ht/μ hydride site is highlighted as a blue sphere. The CHX⋯Ht/μFed dihydrogen contacts within 3 Å are shown, with HX highlighted as purple spheres. The relative energy ranges provided are based on the values given in Table S3.