The ³¹P NMR Chemical Shielding Tensors in Quaternary Metal Thiophosphates, NaNb₂PS₁₀, AgNb₂PS₁₀, Au_0.5Nb₂PS₁₀, and NaSmP₂S₆

Abstract

For quaternary metal thiophosphates, NaNb2PS10, AgNb2PS10, Au0.5Nb2PS10, and NaSmP2S6, the principal elements of the 31P NMR chemical shielding tensor (δ11, δ22, and δ33) are acquired from the nonlinear least-squares fitting the static powder patterns and MAS spectra. Isotropic chemical shift (δiso) and chemical shielding anisotropy (Δδ) have been employed to correlate with the X-ray crystallographic data, the average (P−S) bond length and the average (S−P−S) bond angle deviation from 109.5°, respectively, at the tetrahedrally coordinated phosphorus atoms. On the basis of these successful correlations, the charge transfer from Na, Ag, and Au metals to the (P−S) ligand is discussed and complemented by the band-structure calculation.