Abstract
The excitation of nitrogen 1s electrons has been observed in N2, NO, and N2O by using the electron energy-loss technique at an incident energy of 1.5 keV, and with an energy resolution of 0.075 eV. The energies, widths and vibrational structures of the inner-shell excited states have been obtained. The spectroscopic constants (internuclear separation Re, vibrational constants omega and omega x and quantum defect delta ) of the inner-shell excited states of N2 have been derived and have been found to be similar to those of the equivalent core states. The energies and vibrational structures of the inner-shell excited states of NO and N2O have also been interpreted in terms of the equivalent core model.