Satellite band in the rovibrational spectrum of CO2 in helium droplets -: art. no. 195301

Pulsed infrared (nu approximate to 2350 cm(-1)) laser excitation spectra of CO2 molecules embedded in helium droplets are reported. The spectra exhibit a sharp R(0) rovibrational line accompanied by a weak broader (delta nu approximate to 10 cm(-1)) satellite band, which is shifted by 14 cm(-1) towards higher frequencies. We assign this satellite band to a simultaneous rovibrational excitation of a molecule and its helium solvation shell. The results are rationalized within a model, which includes coupling of the rotational states of a molecule and a ring of He atoms.