Photoelectron spectroscopic studies of polyatomic molecules: Spin-polarized electrons from orientedTdmolecules

This paper presents a theoretical study of angular distribution of spin-resolved electrons ejected by interaction of light in the nonrelativistic, electric dipole approximation with nonlinear molecules oriented in space. A theory, formulated in an earlier paper [N. Chandra, Phys. Rev. A 40, 752 (1989)] by taking full account of the group-theoretical transformation properties of a molecular target, is used to develop explicit expressions for the four parameters [namely, the spin-unresolved differential cross section ${\mathit{d}}^2$σ(${\mathit{m}}_{\mathit{r}}$)/dk^dω for photoionization and the three polarization parameters χ(${\mathit{m}}_{\mathit{r}}$,k,ω), κ(${\mathit{m}}_{\mathit{r}}$,k,ω), and ζ(${\mathit{m}}_{\mathit{r}}$,k,ω) that depend upon the state of polarization ${\mathit{m}}_{\mathit{r}}$ for the ionizing radiation, propagation vector k, and the orientation of the molecule in space] needed to describe the angularly distributed, spin-polarized photocurrent from linear as well as nonlinear molecules of any symmetry corresponding to one of the 32 point groups, oriented in space in their gaseous phase or on liquid (solid) surfaces.