Determination of molybdenum–oxygen bond distances and bond orders by Raman spectroscopy

Abstract A correlation is developed for relating Raman stretching frequencies of molybdenum–oxygen (MoO) bonds to their respective bond distances in molybdenum oxide compounds. MoO bond orders are also related to stretching frequencies. The MoO correlation is expected to offer invaluable insight into the structures of molybdate species in chemical systems which are not amenable to analysis by diffraction or other spectroscopic techniques. In the present study, the correlation is used to predict stretching frequencies for perfect MoO 4 and MoO 6 structures, and to determine MoO bond distances of the MoO 6 octahedron in Ba 2 CaMoO 6 as well as the dehydrated surface molybdate species in MoO 3 /Al 2 O 3 .