Work

Identification of molecular isomers using laser-induced electron diffraction

Year: 2026

Type: article

Abstract: Gas-phase electron diffraction techniques have served as prominent methods for probing the structures of molecules. However, these methods may not be effective in distinguishing structures between molecular isomers due to their limited sensitivity to nonadjacent bond structures and electronic configurations. Laser-induced electron diffraction (LIED) offers a compelling alternative as the yield of the self-imaging electron highly depends on the shape of valence orbitals, thereby creating distinct diffraction patterns for isomers. Here, we present theoretical and experimental evidence demonstrating the capability of LIED to distinguish between n-butane and isobutane. The underlying principle is elucidated through modeling the multiorbital tunnel ionization of the molecules and the subsequent rescattering of the ionized electron with the molecule. Our findings highlight LIED as a powerful technique for identifying molecular isomers and shed light on its potential for simultaneously probing the nuclear and electronic structure of a molecule. Although gas-phase electron diffraction has served as a prominent method for probing molecular structure, it may not be effective in distinguishing structures between molecular isomers. Here, the authors report on laser-induced electron diffraction (LIED) as an alternative approach, showing that it can distinguish between n-butane and isobutane unambiguously due to its sensitivity to both molecular geometry and electronic structure, highlighting its capabilities as a background-free probe for nuclear and electron dynamics in molecules.

Source: Communications Chemistry

DOI: 10.1038/s42004-026-02189-y