Molecular structure determination from x-ray scattering patterns of laser-aligned symmetric-top molecules

Abstract

We investigate the molecular structure information contained in the x-ray diffraction patterns of an ensemble of rigid CF3 Br molecules aligned by an intense laser pulse at finite rotational temperature. The diffraction patterns are calculated at an x-ray photon energy of 20 keV to probe molecular structure at angstrom-scale resolution. We find that a structural reconstruction algorithm based on iterative phase retrieval fails to extract a reliable structure. However, the high atomic number of Br compared with C or F allows each diffraction pattern to be treated as a hologram. Using this approach, the azimuthal projection of the molecular electron density about the alignment axis may be retrieved. © 2009 American Institute of Physics.