SPECTROSCOPIC CONSTANTS OF NH(A1-DELTA) FROM THE C1-PI(UPSILON'=0)-A1-DELTA(UPSILON''-LESS-THAN 3) LASER-INDUCED FLUORESCENCE-SPECTRA

NH(a1Δ, v″ ≤ 3) was produced in a quasi-static exciplex laser photolysis cell from the photodissociation of HN3 at λL = 248 nm. Undispersed laser-induced excitation spectra of the transitions NH(c1Π)-(a1Δ) (0-2) and (0-3) were recorded to determine the band origins ν ̃02 and ν ̃03, ν ̃02 = 24 484.61 ± 0.1 cm-1 ν ̃03 = 32 6+2.60 ± 0.07 cm-1; the vibrational constants ωe, ωeχe, and ωeγe, ωe = 3331.15 ± 0.40 cm-1ωeχe= 74.84 ± 0.30 cm-1ωeγe = 0.40 ± 0.06cm-1; and the rotational constants BΔ, DΔ, and HΔ of the (a1Δ) state, BΔ (ν″ =2) = 15.203 ± 0.002 cm-1DΔ (ν″ =2) = (1.61 ± 0.03)· 10-3cm-1HΔ (ν″ =2) = (0.9 ± 0.07)· 10-7cm-1BΔ (ν″ =3) = 14.599 ± 0.003 cm-1DΔ (ν″ =3) = (1.56 ± 0.06)· 10-3cm-1. These spectroscopic constants are compared to the values available in the literature. © 1990.