光腔衰荡光谱技术研究AsH2自由基: <italic>Ã</italic><sup>2</sup><italic>A</italic><sub>1</sub>(000)−X<sup>~2</sup><italic>B</italic><sub>1</sub>(000)

The absorption spectra of AsH₂ radical were recorded in 19870―20250 cm⁻¹ by cavity ringdown spectroscopy. The AsH2 radicals were produced by pulsed DC discharge of a gas mixture of AsH3 in argon. Based on the previous studies, the obtained spectra can be assigned as the vibronic transition: òA₁ (000)–X ²B₁(000). Rotational assignments and least square fittings for about 777 rotational lines with K_a´≤5 and N´≤10 were carried out, and the rotational term values and the molecular parameters were also determined with reasonably high precision. The perturbations observed for the upper state were briefly analyzed and discussed.