Carbon K‐shell electron energy loss spectra of 1‐ and 2‐butenes, trans‐1,3‐butadiene, and perfluoro‐2‐butene. Carbon–carbon bond lengths from continuum shape resonances

摘要: Electron energy loss spectra of 1‐butene, cis‐2‐butene, trans‐2‐butene, trans‐1,3‐butadiene, and perfluoro‐2‐butene in the region carbon K‐shell (C 1s) excitation ionization have been recorded under dipole‐dominated inelastic electron scattering conditions. The features observed below C 1s I.P. butenes butadiene are assigned to promotions electrons unoccupied valence (π*) Rydberg orbitals while broad above edge σ(C–C) shape resonances. These spectra, along with other hydrocarbons, used demonstrate that there is a quantitative relationship between carbon–carbon bond lengths location σ resonances relative threshold (I.P.). spectrum demonstrates dramatic potential barrier effects, namely suppression transitions strong enhancement σ(C–F) 1s...