Core state vibrational excitations and symmetry breaking in the CK and OK emission spectra of CO2

摘要

The CK and OK emission spectra of gaseous CO2have been recorded in high resolution. From a Franckndash;Condon fit to the vibrational structure of the spectra, it is shown that C1sionization leads to a bond length shortening of 2.0 pm, while O1sionization mainly results in a displacement of the carbon atom of 5 pm, thereby breaking theDinfin;hsymmetry of the molecule. The high resolution allowed the natural lifetime width of the O1svacancy state to be determined to 0.07 eV and by the use of an accurate calibration procedure the adiabatic xhyphen;ray transition energies were determined. These energies were used to obtain accurate binding energies of the core electrons. The O1sbinding energies in CO2were determined to 297.651 and 541.07 eV, respectively.