Inner-shell electron energy-loss spectroscopy of SF6 at very high momentumtransfer

Non-dipole S 2p and S 2s core excitation of SF, has been studied using inel astic electron scattering with variable scattering angles and impact energi es (momentum transfer (K), 0.9 < K-2 < 113 a.u.(-2)). A non-dipole excitati on at 181 eV is found to be the dominant S 2p spectral feature at large mom entum transfer. A variable impact energy, fixed-K study shows that the firs t Born approximation fails under low impact energy, large scattering angle conditions. This study illustrates the importance of exploring a wide range of the inelastic scattering surface to ensure proper understanding of mole cular spectroscopy and scattering dynamics. (C) 1999 Elsevier Science B.V. All rights reserved.