The bending vibrational levels in C2D2 (X̃ 1Σ+g)

Abstract

Improved sets of data have been recorded and analyzed in order to study the bending rovibrational energy levels of C₂D₂, in the regions of the ν₅–ν₄ difference band (FIR) and of the ν₅ fundamental band (IR). A matrix model is setup to deal with a Darling–Dennison coupling between sets of bending levels as well as with the usual l‐type resonances. A simultaneous fit of the new data together with earlier microwave measurements produces an extended set of very accurate parameters, including for the first time in C₂D₂ s₄₅ and q^k_t.