SOLIDS CONTAINING METHYLHALOPHOSPHONIUM CATIONS [(CH3)NPX4-N(+)] (N=1-3 X = CL, BR) - AN INVESTIGATION USING MAGIC-ANGLE SPINNING NMR-SPECTROSCOPY

A selection of complexes containing [(CH3)nPX4-n+] cations (X = Cl, Br) have been investigated by magic-angle spinning (MAS) P-31 and B-11 NMR spectroscopy. Qualitative information about ionic motion in these systems is derived from the observed linewidths, which are dependent upon the nature of the anions present in the lattices. Isomers of [(CH3)PCl3+Cl-] and [(CH3)2PCl2+Cl-] are detected, confirming previous Raman spectroscopic observations. The mixed-halogen cations [(CH3)PCl2Br+], [(CH3)PClBr2+] and [(CH3)2PClBr+] are also observed, complexed with both single-halide and polyatomic anions. Differences in NMR linewidths are again noted. These results are compared with Raman studies on the same complexes and contrasted with a similar investigation of the [PClnBr4+-n] (0 less-than-or-equal-to n less-than-or-equal-to 4) system.