Compound state electron spectra of simple molecules

Abstract
Compound negative ion states of molecules N2, CO, NO, O2, CO2, N2O and NO2have been detected as structure in the total electron scattering cross-sections, interpreted in terms of the Beutler–Fano equation, and partially identified by comparison with isoelectronic species : N2-2ІІg, 2 eV ; CO-2II, 1·5 eV ; NO-1Ʃ+, 1 eV ; O2-2IIu, 0·8 eV. The performance of the inverse first-power electrostatic analyser is treated ; it compares satisfactorily with theory provided that preliminary analysis is performed ; otherwise ‘false resonances’ or ghosts may occur.