Characterization of the Room-Temperature Structure of SnP₂O₇ by ³¹P Through-Space and Through-Bond NMR Correlation Spectroscopy

Abstract

The room-temperature structure of SnP 2 O 7 has been investigated using various one- and two-dimensional (1- and 2D) magic-angle spinning (MAS) NMR experiments. We show that 31 P homonuclear through-bond and through-space correlation NMR spectroscopies allow us to discriminate between the 12 possible space group symmetries of the structure. In particular, the 31 P 2D refocused INADEQUATE experiment allows us to resolve an impressive number of distinct 31 P resonances, showing that the asymmetric unit contains at least 49 different P 2 O 7 groups with two inequivalent P sites. The results suggest that the symmetry of the SnP 2 O 7 room-temperature structure is monoclinic with space group P 2 1 or Pc .