Resonance Raman spectra measured for ClNO photoexcited at 212.5, 219, and 222 nm produce evidence that the strong transition at the vacuum ultraviolet end of the merged A band system dominates to wavelengths as long as 222 nm. The spectral resolution is sufficient to enable definitive assignments of excited vibrational levels in the ground electronic state, several of which have not been previously observed. A curvilinear coordinate model of the ground state potential surface around the Franck-Condon region has been constructed. This model yields vibrational eigenvalues in excellent agreement with all known transitions.