Distribution of internal states of [formula omitted]) from photodissociation of nitric acid

• Published in: Chemical physics letters Vol. 257; no. 5; pp. 481 - 486
• Main Authors: Leu, Gen-Hou, Hwang, Chun-Wei, Chen, I-Chia
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1996
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/0009-2614(96)00567-2

We detected fluorescence of OH (A 2Σ +− X 2Π) from nitric acid photolyzed at 193 nm. Transitions for spin-orbit states are resolved; the population ratio of these states is Π 3 2 /Π 1 2 ≈ 1.1 ± 0.1 . About 3% of available energy is distributed to rotation of the OH fragment; no vibrationally excited OH was observed. The transitional energies of OH and NO 2 are estimated from the Doppler widths to be 2332 and 861 cm −1, respectively. These results indicate about 87.8% of the excess energy to be directed to internal energy of NO 2. The experimental data indicate that NO 2 may be produced in an electronically excited state.