Impact of Reduction on the Properties of Metal Bisdithiolenes: Multinuclear Solid-State NMR and Structural Studies on Pt(tfd)2 and Its Reduced Forms

Transition-metal dithiolene complexes have interesting structures and fascinating redox properties, making them promising candidates for a number of applications, including superconductors, photonic devices, chemical sensors, and catalysts. However, not enough is known about the molecular electronic origins of these properties. Multinuclear solid-state NMR spectroscopy and first-principles calculations are used to examine the molecular and electronic structures of the redox series [Pt(tfd)2]z– (tfd = S2C2(CF3)2; z = 0, 1, 2; the anionic species have [NEt4]+ countercations). Single-crystal X-ray structures for the neutral (z = 0) and the fully reduced forms (z = 2) were obtained. The two species have very similar structures but differ slightly in their intraligand bond lengths. 19F−195Pt CP/CPMG and 195Pt magic-angle spinning (MAS) NMR experiments are used to probe the diamagnetic (z = 0, 2) species, revealing large platinum chemical shielding anisotropies (CSA) with distinct CS tensor properties, despite ...