Imaging an isolated water molecule using a single electron wave packet

Abstract

Observing changes in molecular structure requires atomic-scale Ångstrom and femtosecond spatio-temporal resolution. We use the Fourier transform (FT) variant of laser-induced electron diffraction (LIED), FT-LIED, to directly retrieve the molecular structure of ${\mathrm{H}}_2{\mathrm{O}}^{+}$ with picometre and femtosecond resolution without a priori knowledge of the molecular structure nor the use of retrieval algorithms or ab initio calculations. We identify a symmetrically stretched ${\mathrm{H}}_2{\mathrm{O}}^{+}$ field-dressed structure that is most likely in the ground electronic state. We subsequently study the nuclear response of an isolated water molecule to an external laser field at four different field strengths. We show that upon increasing the laser field strength from 2.5 to 3.8 V/Å, the O-H bond is further stretched and the molecule slightly bends. The observed ultrafast structural changes lead to an increase in the dipole moment of water and, in turn, a stronger dipole interaction between the nuclear framework of the molecule and the intense laser field. Our results provide important insights into the coupling of the nuclear framework to a laser field as the molecular geometry of ${\mathrm{H}}_2{\mathrm{O}}^{+}$ is altered in the presence of an external field.

References in corpus (5)

• Imaging the Photochemical Ring-Opening of 1,3-Cyclohexadiene by Ultrafast Electron Diffraction
• Imaging an aligned polyatomic molecule with laser-induced electron diffraction
• Strong field ionization to multiple electronic states in water
• Influence of orbital symmetry on diffraction imaging with rescattering electron wave packets
• Imaging the Renner-Teller effect using laser-induced electron diffraction

Cited by in corpus (4)

• Molecular structure retrieval directly from laboratory-frame photoelectron spectra in laser-induced electron diffraction
• Quantum interference and imaging using intense laser fields
• Generating high density molecular jets of complex neutral organic molecules using micro-sized Tesla valves
• Laser-induced electron diffraction in the over-the-barrier ionization (OBI) regime