The emission spectroscopy of the [formula omitted] system of CD

Abstract

The visible spectrum of CD has been investigated at high resolution between 24,500 and 27,500cm−1 using a high accuracy dispersive optical spectroscopy technique. The CD molecules were produced and excited in a stainless steel hollow-cathode lamp with two anodes and filled with a mixture of He buffer gas and CD4. The emission from the discharge was observed with a plane grating spectrograph and recorded by a photomultiplier tube. The 0–0, 1–0 and 1–1 bands of the B2Σ-–X2Π transition have been registered and measured, while 2–0 and 2–1 absorption bands (Herzberg and Johns, 1969) have been reanalyzed. The current data were elaborated with help of recent X2Π ground state parameters reported by Zachwieja et al. (2012) from investigation of the A2Δ–X2Π transition. This way, the improved spectroscopic constants for the B2Σ- state of CD have been provided as follows: νe=26,050.787(11)cm−1, ωe=1653.019(25)cm−1, ωexe=123.899(12)cm−1, Be=7.08296(32)cm−1, αe=0.30741(84)cm−1, and γe=-0.10727(42)cm−1.