Absolute Generalized Oscillator Strength Profile of Negative Ion Resonance at 8.9eV in C₂F₆

A temporary negative ion resonance at 8.9eV in C₂F₆ has been clearly identified using angle-resolved electron energy loss spectroscopy at 2.5keV impact energy, and can be attributed to electron capture into 1²a_lu, 1²a_1g, 2²a_2g, and 1²e_g virtual molecular orbitals. The corresponding absolute generalized oscillator strength profile is found to have a shape characteristic of non-dipole interaction with the maximum K ～ 0.8a.u. of momentum transfer.