Electron diffraction from laser-aligned beams of large hydrated molecules

Abstract

We consider X-ray or electron diffraction from a molecular beam of hydrated proteins. These are aligned by the polarized field of a powerful continuous infrared laser. The laser power, temperature and molecular size needed to obtain sufficient alignment accuracy for sharp diffraction patterns is estimated using a thermal average, and the resulting Dawson integral compared with the estimate based on equipartition used in our previous work. The conditions determined allow sub-nanometer resolution charge-density maps to be reconstructed from phased diffraction patterns, so that the secondary structure of the proteins can be observed.