Cross sections and asymmetry parameters in gas-phase photoionization of C₆₀

Calculations are carried out on the photoionization of C₆₀ molecules in the gas phase, in particular, the photoionization of its highest occupied molecular orbital leading to the formation of C₆₀⁺ in the ²H_u state. The computational treatment employs the undistorted orbitals of the neutral molecule and solves the coupled scattering equations for the ejected electron in the field of the molecular ion by using the correct static-exchange interaction within a polyatomic Schwinger variational method with Padé corrections. The total cross section and photoelectron angular distributions show marked resonant features from the threshold up to photon energy of about 30 eV. In the present calculations, all resonances are one-electron resonances of the outgoing electron and are very reminiscent of those predicted for electron-scattering processes from neutral C₆₀. The physical implications of this result are analyzed and discussed.