Investigation of the structure, bonding, vibrational frequencies and stability by ab initio calculations of H3BPH3, H3BPHF2, and H3BPF3

Utilizing ab initio calculations with various basis sets with electron correlation, the structural parameters, vibrational frequencies, and nature of the bonding and stability of the phosphine-borane complexes H3BPH3, H3BPHF2 and H3BPF3 have been ascertained. When appropriate, the theoretical results have been compared with the experimental values. At the MP2/6-311++G** level, the calculated B-P distance is nearly 0.020 Angstrom too long and the P-F distance 0.025 Angstrom too long for both fluorine-containing molecules. Similarly, for the simple PF3 molecule, the calculated P-F distance is too long by 0.024 Angstrom with this basis set at the given level of calculation. (C) 1997 Elsevier Science B.V.