title: R-matrix calculation of low-energy electron collisions with uracil.
abstract: R-matrix calculations on electron-uracil collisions are presented within the static exchange, static exchange plus polarization, and close-coupling approximations. Particularly as input for the close-coupling calculations, a series of target calculations is performed which considers low-lying singlet and triplet excited states of the uracil target. The scattering calculations find three low-lying shape resonances of (2)A(") symmetry and three higher-energy Feshbach resonances of (2)A(') symmetry. In both symmetries the precise resonance parameters are found to be sensitive to the treatment of polarization effects employed. Cross sections are presented for both elastic scattering and electronic excitation. Comparisons are made with energy-dependent, differential cross section measurements at 90 degrees angle and good agreement is found for scattering energies above 0.5 eV.
authors.affiliation: Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom.
authors.forename: Amar
authors.initials: A
authors.lastname: Dora
authors.forename: Jonathan
authors.initials: J
authors.lastname: Tennyson
authors.forename: Lilianna
authors.initials: L
authors.lastname: Bryjko
authors.forename: Tanja
authors.initials: T
authors.lastname: van Mourik
mesh_terms: D003198:Computer Simulation; D004583:Electrons; D008958:Models, Molecular; D014498:Uracil / Q000737:chemistry*
chemical_list: D014498:Uracil