Knowledge Bank

Vibrational level in the van der Waais intermolecular potential of the glyoxal(X1Ag). Ar complex were directly observed by stimulated emission spectroscopy. These van der Waals vibrational levels can be assigned to the fundamental and overtone levels of the Ar-glyoxal stretching and the two bending modes. These van der Waals vibrational levels will allow us to model the intermolecular potential with previously unattainable accuracy. The stimulated emission spectroscopy may also be used to study all the vibrational levels in the X state with nonvanishing Frenck-Condon factors from the electronic excited state with $0.04cm-1$ resolution. The width of single rotational lines of three glyoxal vibrational levels were determined to be $-0.2cm-1$ for the 41 end 81 levels and for the 5, level. These widths arise from vibrational predissociation of the complex.