Formation of a simple hafnium methylidene complex by reaction of methyl fluoride with laser-ablated hafnium atoms

The methylidene hafnium complex (CH2=HfHF) is formed by reaction of methyl fluoride with laser-ablated hafnium atoms and isolated in a solid argon matrix. The higher Hf-H and C-Hf stretching frequencies for CH2=HfHF than those of CH2=ZrHF are attributed to the shortened bonds for the heavier metal atom owing to relativistic effects. The singlet CH2=HfHF ground state molecule shows evidence of an a-hydrogen agnostic interaction. In contrast to the cases of Ti and Zr, the most likely initial CH3-HfF intermediate was not trapped in the matrix, as a-hydrogen shift led directly to the CH2=HfHF product.