Lineshape analysis of impurity Rydberg transitions in van der Waals solids: derivation of intermolecular potentials

Fluorescence depletion spectra of the A 2Σ+(3sσ) Rydberg fluorescence of NO in rare-gas and hydrogen matrices are reported in the 0.9–1.3 eV region. Bands due to the Rydberg–Rydberg A 2Σ+(3sσ)–C 2Π(3pπ) and A 2Σ+(3sσ)–D 2Σ+(3pσ) transitions are observed. These spectral features are combined with ground-state absorption data of the A, C and D states and with A-state fluorescence data to generate a set of intermolecular potentials describing the impurity–matrix interaction in each state. The effective mode and harmonic approximations are made and the semiclassical reflection method is used.