Feshbach projection-operator calculation of the resonant states of H2-

Abstract
A formulation of the Feshbach projection-operator technique for a three-electron system is presented which renders practicable the calculation of the H2-resonance positions, and ultimately their widths, by standard configurational interaction methods. Striking and hitherto unidentified resonances in the 0 to 12 eV region have been discovered and these may lead to a more complete interpretation of the existing experimental results.