Argon matrix effect on the geometry and infrared spectrum of the agostic complexes H2CNbH2 and H2CTaH2: A theoretical study

An argon matrix effect on the geometry and infrared spectrum of the agostic complexes H2CNbH2 and H2CTaH2 is simulated within the framework of IEF-PCM at the B3LYP and BPW91 levels of theory with substantive basis sets. Both the complexes are optimized to a pyramidal Cs structure by the BPW91/IEF-PCM calculations, in which the two metal hydrogen bonds are identical. This Cs structure is in excellent agreement with the structure inferred from the experimental matrix infrared spectra [H.-G. Cho, L. Andrews, J. Phys. Chem. A 110 (2006) 38], emphasizing importance of the matrix effect modeling in interpretation of the experimental spectra of the complexes.