TWO PHOTONS EXCITED 4d RYDBERG STATE OF AsH₃

In this paper, by using resonance enhanced (2+1) multiphoton ionization (REMPI) of AsH₃ and detecting the daughter molecular ions AsH⁺ and As⁺, a long progression discrete structure was obtained from 267 to 291 nm, which obeys the formula \nu₀(cm^-1)=68875.3+504.1v′₂+5.26v′²₂. Analysis of the spectrum has revealed that it belongs to 4d Rydberg state transition. Our assignment yields the 4d Rydberg state parameters T_e′=67881.1 cm^-1, \omega_e′=495.1 cm^-1 and \delta=0.962. Finally the 4d Rydberg state structure of AsH₃ was discussed.