NMR Magnetic Shielding in Transition Metal Compounds Containing Cadmium, Platinum, and Mercury

In this article, we delve into the intricate behavior of electronic mechanisms underlying NMR magnetic shieldings σ in molecules containing heavy atoms, such as cadmium, platinum, and mercury. Specifically, explore PtXn−2 (X = F, Cl, Br, I; n 4, 6) XCl2Te2Y2H6 Cd, Hg; Y N, P) molecular systems. It is known that leading responsible for relativistic effects on are well characterized by linear response with elimination small components model (LRESC). study, present results obtained from innovative LRESC-Loc model, which offers same outcomes LRESC but employs localized orbitals (LMOs) instead canonical MOs. These LMOs provide a chemist’s representation atomic core, lone pairs, bonds. The whole set can be expressed terms both non-ligand-dependent ligand-dependent contributions. We elucidate origins trends behaviors exhibited these diverse aforementioned PtX4−2 molecules, predominant mechanism well-established one-body spin–orbit (σSO(1)) mechanism, while paramagnetic mass–velocity (σMv) Darwin (σDw) contributing also demand consideration. However, PtX6−2 σ(Mv/Dw) contribution surpasses SO(1) thus influencing overall As complexes Cd Hg, contributions exhibit similar magnitudes when nitrogen substituted phosphorus. only discrepancy arises σSO(1) contribution, changes sign between two due to bond metal tellurium atoms.