F(2)BMF (M = B and Al) Molecules: A Matrix Infrared Spectra and Theoretical Calculations Investigation

Reactions of laser-ablated B and Al atoms with BF(3) have been explored in the 4 K excess neon through the matrix isolation infrared spectrum, isotopic substitutions and quantum chemical calculations. The inserted complexes F(2)BMF (M = B, Al) were identified by anti-symmetric and symmetric stretching modes of F-B-F, and the F-(11)B-F stretch modes are at 1336.9 and 1202.4 cm(−1) for F(2)(11)B(11)BF and at 1281.5 and 1180.8 cm(−1) for F(2)(11)BAlF. The CASSCF analysis, EDA-NOCV calculation and the theory of atoms-in-molecules (AIM) are applied to investigate the bonding characters of F(2)BBF and F(2)BAlF molecules. The bonding difference between boron and aluminum complexes reveals interesting chemistries, and the FB species stabilization by a main group atom was first observed in this article.