Theoretical prediction of geometries and vibrational infrared spectra of ruthenium oxide molecules

Abstract We present computations of the optimized geometries and the corresponding vibrational frequencies of the molecules RuO 2 , RuO 3 , and RuO 4 . The computations utilize the Gaussian 90 Program Package, and they are based on the use of effective core potentials. In the case of RuO 2 , we obtain a closed shell singlet configuration with a bond angle of 150.6° and also a close and, possibly, lower lying triplet state with a bond angle of 133.7°. The trioxide is trigonal planar and the tetroxide is tetrahedral. On the whole, the calculated vibrational frequencies and geometries agree well with experimental values.