Extraction of geometrical structure of ethylene molecules by laser-induced electron diffraction combined with ab initio scattering calculations

Abstract

Author(s): Ito, Y; Carranza, R; Okunishi, M; Lucchese, RR; Ueda, K | Abstract: We measured angle-resolved high-energy electron spectra emitted from C2H4 in an intense laser field, extracted field-free electron-ion elastic scattering differential cross sections (DCSs) according to quantitative rescattering theory, and obtained molecular contrast factors (MCFs) subtracting the incoherent sum of DCSs of all the atoms in the molecule. Comparing the results with ab initio scattering calculations and employing least-squares fitting, we have extracted the C-C and C-H bond lengths of the molecule with ∼5% uncertainty. This approach opens the way to retrieve the structure of hydrocarbon molecules, potentially at high temporal resolution, employing low collision energies where electron scattering is sensitive to the hydrogen atoms; and where the independent atom model calculations may fail to reproduce the experimentally extracted MCF.