Filling a Gap: The Coordinatively Saturated Group 4 Carbonyl Complexes TM(CO)₈ (TM=Zr, Hf) and Ti(CO)₇.

ABSTRACT: Homoleptic Group 4 metal carbonyl cation and neutral complexes were prepared in the gas phase and/or in solid neon matrix. Infrared spectroscopy studies reveal that both zirconium and hafnium form eight-coordinate carbonyl neutral and cation complexes. In contrast, titanium forms only the six-coordinate Ti(CO)₆ ⁺ and seven-coordinate Ti(CO)₇ . Titanium octacarbonyl Ti(CO)₈ is unstable as a result of steric repulsion between the CO ligands. The 20-electron Zr(CO)₈ and Hf(CO)₈ complexes represent the first experimentally observed homoleptic octacarbonyl neutral complexes of transition metals. The molecules still fulfill the 18-electron rule, because one doubly occupied valence orbital does not mix with any of the metal valence

SUBMITTER: Deng G 

PROVIDER: S-EPMC7496348 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature