Synthesis and characterization of the phosphorus halide-boron halide complexes X3PBY3 (X = Cl, Br, I; Y=Br, I) by P-31 MAS NMR, IR, and Raman spectroscopy and the crystal structure of Br3PBBr3

The phosphorus halide-boron halide complexes X3PBY3 (X = Cl, Br, I; Y = Br, I) were prepared and characterized by Raman and IR spectroscopy. Density f unctional theory (B3LYP) was applied to calculate structural and vibrationa l data. Assignments of the vibrational normal modes for these Lewis acid-ba se adducts were made on the basis of their Raman and IR spectra in comparis on with computational results. The compounds Cl3PBBr3, Br3PBBr3, I3PBBr3, a nd I,PBI, were also studied by solid-state P-31 MAS NMR spectroscopy. Secon d-order P-31-Br-79,Br-81 dipolar coupling effects were observed in the P-31 MAS NMR spectrum of Br3PBBr3. The molecular structure of Br3PBBr3 was dete rmined by X-ray diffraction.