The electronic spectrum of vanadium monoxide across the visible: new bands and new insight.
Resonance enhanced multiphoton ionization spectra of vanadium monoxide (VO) have been measured in the 16,000-23,300 cm(-1) region. A series of intense peaks, identified as the VO C (4)Sigma(-) (v('))-X (4)Sigma(-) (v(")=0) progression, has been recorded up to v(')=7 and vibrational and rotational parameters have been extracted by simulation of the rotationally resolved spectra. Additional weak transitions in the spectrum are assigned to the 2 (2)Pi-X (4)Sigma(-) spin-forbidden band system allowing the first direct determination of a spin-orbit coupling constant within the doublet spin manifold of VO. Together, the spectra provide absolute energies for several doublet electronic states with respect to the X (4)Sigma(-) ground state. A further vibronic progression observed at 22,000 cm(-1) is assigned as a second spin-forbidden excitation from the X (4)Sigma(-) ground state to a (2)Pi state which has not previously been characterized.
Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
W Scott
WS
Hopkins
Suzanne M
SM
Hamilton
Stuart R
SR
Mackenzie