The infrared spectrum of the AsD radical in its XΣ state, recorded by laser magnetic resonance

The infrared spectrum of the AsD radical in the X³Σ⁻ ground state has been recorded using CO laser magnetic resonance. The radical was formed by the reaction between D atoms and arsenic powder. Low-N transitions in the fundamental band and in the (2-1) and (3-2) hot bands have been detected. Hyperfine structure from the ⁷⁵As nucleus (I = 3/2) is seen on many of the resonances. These measurements have been combined with information from previous measurements of rotational transitions at sub-millimeter wavelengths [H. Fujiwara, K. Kobayashi, H. Ozeki, S. Saito, A.I. Jaman, J. Chem. Soc. Faraday Trans. 93 (1997) 1045-1051] to determine an extended and improved set of molecular parameters for ⁷⁵AsD. Comparison is made with corresponding parameter values for AsH.