Dora Amar, Tennyson Jonathan, Bryjko Lilianna, van Mourik Tanja
Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom.
J Chem Phys. 2009 Apr 28;130(16):164307. doi: 10.1063/1.3119667.
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.
本文给出了在静态交换、静态交换加极化以及密耦近似下对电子与尿嘧啶碰撞的R矩阵计算。特别是作为密耦计算的输入，进行了一系列靶计算，其中考虑了尿嘧啶靶的低激发单重态和三重态。散射计算发现了三个具有(2)A(")对称性的低形状共振以及三个具有(2)A(')对称性的较高能量的费什巴赫共振。在这两种对称性中，发现精确的共振参数对所采用的极化效应处理很敏感。给出了弹性散射和电子激发的截面。与90度角的能量相关微分截面测量结果进行了比较，发现在散射能量高于0.5 eV时两者吻合良好。
