Neutral rare-gas containing charge-transfer molecules in solid matrices. III. HXeCN, HXeNC, and HKrCN in Kr and Xe

Abstract

The synthesis of novel rare-gas compounds HXeCN, HXeNC, and HKrCN is reported. HKrCN represents the first stable compound with a Kr–C bond. The novel molecules are formed in solid Xe and Kr by first photolyzing monomeric HCN with a 193 nm ArF laser at 7.5 K. The photolysis produces isolated hydrogen atoms and CN radicals as evidenced by IR spectroscopy and laser induced fluorescence. Annealing of the Kr matrix at ∼30 K and Xe matrix at ∼50 K activates the hydrogen atoms, and they react with rare-gas atoms surrounding the CN radicals producing the rare-gas compounds, which are characterized in this work by means of IR spectroscopy and ab initio calculations. Other products observed are HNC and H2CN. Infrared induced photochemical conversion of HXeNC to HXeCN is accomplished by exciting the Xe–H and C–N stretching fundamentals of HXeNC. The existence of low barrier between these two distinct isomers is confirmed by the ab initio calculations.