High-resolution study of the ν1 + ν2 and ν2 + ν3 strongly interacting bands of D2Se

A high-resolution Fourier transform spectrum of the D₂^MSe species (M = 82, 80, 78, 77, and 76) in the region 2300-2500 cm⁻¹ was recorded for the first time and assigned. On the basis of these experimental data, rotation-vibration energies of the (1 1 0) and (0 1 1) vibrational states were fitted, and band centers, and rotational, centrifugal distortion, and resonance interaction parameters were determined for the main D₂⁸⁰Se species. The obtained set of 32 fitted parameters reproduces the 647 rotation-vibration energies with a rms deviation of 0.00024 cm⁻¹. The ν₁ + ν₂ and ν₂ + ν₃ bands of the other four isotopic species are analyzed as well.