Solid-state NMR studies of some tin(II) compounds

High-resolution NMR spectra of spin-1/2 nuclei, particularly Sn-119 and insolid tin(II) phosphite, SnHPO3,and tin(II) phosphate, SnHPO4, are presented. The results are discussed in relation to the crystal structures. Spinning sideband analysis has been carried out for both nuclei, giving information on the shielding tensors. Satellite peaks allow the indirect Sn,Sn coupling constants to be determined. Surprisingly large values of 2600 +/- 200 Hz and 4150 +/- 200 Hz are reported for SnHPO3 and SnHPO4 respectively. The satellite peaks were investigated by using a single Hahn echo for each refocusing time, which showed that the observed splittings result from Sn-119, Sn-117 coupling. For SnHPO3, the calculated relative intensities of the satellites for six intra-layer coupling interactions are in agreement with the experiment values, but for SnHPO4 the coupling appears to be inter-layer in nature. Tin-119 (and in one case phosphorus-31) shielding tensor data derived from MAS NMR are also reported for four other crystalline tin(II) compounds, namely tin diphosphate, tin oxalate, tin sulphate and calcium tin ethylenediamine tetraacetate. (C) 2004 Elsevier Inc. All rights reserved.