Vibrational excitation of CO, CO2 and N2O by Li+ impact in the energy range from 70 eV to 1500 eV

Vibrational excitation of CO, CO2 and N2O by Li+ impact was studied with an ion energy-loss spectrometer. The excitation takes place in strongly forward scattering above 400 eV, and absolute total cross sections of excitation are obtained easily. For CO, the cross sections of 0→1 and 0→2 excitation are obtained. For CO2, the cross sections for the excitation of (010), (020), (001) and (011) levels are determined. The excitation of the symmetric stretching mode (100) is not observed. For N2O, the excitation cross sections of (100), (010), (001), (002) and (101) levels are obtained. The experimental results are compared with the first Born approximation, and a possibility of determining the infrared intensities is discussed. (author)