Vibrational structure of core to Rydberg state excitations of carbon dioxide and dinitrogen oxide

The near-edge x-ray absorption spectra of dinitrogen oxide and carbon dioxi de have been measured with ultra high resolution and high statistical accur acy at the N 1s and O 1s edges, and at the C 1s and O 1s edges in N2O and C O2, respectively. The assignment of the peaks in the spectra is achieved vi a the analysis of the quantum defects of the Rydberg states, the use of the core-equivalent model and a comparison with previous photoabsorption and f ragment ion spectra. New high-resolution spectra are provided for the O 1s excitations of CO2, and several new states are observed at the oxygen edge of N2O.