Are matrix isolated species really “isolated”? Infrared spectroscopic and theoretical studies of noble gas-transition metal oxide complexes

In this review, we summarize our recent results on matrix isolation infrared spectroscopic studies and theoretical investigations of noble gas-transition metal oxide complexes. The results show that some transition metal oxide species trapped in solid noble gas matrices are chemically coordinated by one or multiple noble gas atoms forming noble gas complexes and, hence, cannot be regarded as isolated species. Noble gas coordination alters the vibrational frequencies as well as the geometric and electronic structures of transition metal oxide species trapped in solid noble gas matrixes. The interactions between noble gas atoms and transition metal oxides involve ion-induced dipole interactions as well as chemical bonding interactions. Periodic trends in the bonding in these noble gas-transition metal complexes are discussed.