Abstract

Van der Waals molecules are weakly bound complexes that serve well as prototype systems for vibrational dynamics and unimolecular decay studies. Vibrational predissociation has been examined in a number of van der Waals molecules.^1-3 An interesting complex is the nitric oxide dimer. This is the only case of vibrational predissociation in a van der Waals complex for which there are complementary time-and frequency-domain measurements. Previous investigations of (NO)₂ infrared photodissociation dynamics revealed a mode dependence of the NO product appearance rate when the v₁ or v₅ NO stretching modes were excited,^4-8 The lifetime of the excited dimer was 880 ± 260 ps and 39 ± 8 ps after v₁ (1868 cm⁻¹·) and v₅ (1789 cm⁻¹) excitations, respectively. Based on these results one should anticipate dramatic effects to be observable lor excitations in the NO overtone regions around 3500-3800 cm⁻¹.

© 1991 Optical Society of America