Circular dichroism in the angular distribution of photoelectrons from oriented CO molecules

Abstract

Theoretical predictions of a new phenomenon arising in photoelectron emission from oriented molecules by circularly polarized light have been experimentally verified for CO. For a special geometry photoelectron-intensity differences occur upon reversal of photon helicity. The measured asymmetries (up to 80%) show good agreement with an ab initio calculation at photon energies between 20 and 40 eV. Theoretically, the new manifestation of circular dichroism is already obtained in the pure electric dipole approximation without inclusion of spin-orbit interaction.