New emission spectrum of carbon monoselenide

Potential Energy Curves and Lifetimes of Low-Lying Excited Electronic States of CSe Studied by Configuration Interaction Method

“…The spectroscopic parameters of all the bound and quasibound Λ–S states were obtained and the results are listed in Table , including adiabatic transition energies T e , harmonic vibrational frequencies ω e , anharmonic terms ω e x e , rotational constants B e , and equilibrium distance R e . For the ground X 1 Σ + state, a 3 Π, and A 1 Π states, our calculated spectroscopic constants agree well with previous experimental and theoretical results ,− , (Table ). The other states have been neither experimentally observed nor theoretically investigated in the literature.…”

“…Because only the v a ′ = 0 vibrational level of a 3 Π 1 is free from perturbations by other crossing states, the ω e and ω e x e values of the a 3 Π 1 state could not be experimentally determined and only the T e , B e , and R e parameters of the v a ′ = 0 level were obtained. 7,8 Our theoretical T e , B e , and R e values of a 3 Π 1 are 24660 cm −1 , 0.5579 cm −1 , and 1.7281 Å, respectively, agree well with latest experimental results 8 of 24460 cm −1 , 0.5474 cm −1 , and 1.722 Å.…”

“…The large equilibrium distance of A′ 1 Σ + also causes the largest Einstein coefficients, A v′v″ , to correspond to the v″ = 8−17 vibrational levels of X 1 Σ + and the v′ = 0−4 vibrational levels of A′ 1 Σ + . Our calculated T 00 of a 3 Π 0+ −X0 + , a 3 Π 1 −X0 + , and A 1 Π−X 1 Σ + transitions are 24327, 24563, and 35069 cm −1 , respectively, which agree well with the experimental values of 24091.3, 7 24407.0, 7 and 35136.414 cm −1 . 27 For the A′ 1 Σ + −X 1 Σ + transition, the T 00 is calculated to be 31994 cm −1 , but the experimental T 00 is not yet known.…”

“…This is one possible reason that the 0−0 band of the a 3 Π−X 1 Σ + band system could be easily observed in previous experiments. 7,8 The crossings between A 1 Π and the singlet states, 1 1 Δ, 3. The spin−orbit matrix elements display similar behaviors for the coupling between the a 3 Π state and the a′ 3 Σ + , d 3 Δ, e 3 Σ − , 1 1 Δ, or 1 1 Σ − states, which first gradually increase as the C−Se bond length increases and then decrease rapidly at large internuclear distance.…”

“… a For the experimental values, the uncertainty of the measurement is given in parentheses. b Reference . c Reference . d Reference . e Reference . f Reference . g Reference . h Reference. i Reference . …”