Ultra accurate measurements and ab initio calculations of collisional effects in pure D2 .

Abstract : We present our experimental spectra of the very weak S(2) transition from the 2–0 band of molecular deuterium, measured with a frequency-stabilized cavity ring-down spectroscopy (FS–CRDS) assisted by the optical frequency comb (OFC). Experimental collisional broadening and shifting are compared with results of ab initio quantum scattering calculations.