Maul R, Preuss M, Ortmann F, Hannewald K, Bechstedt F
Institut für Festkörpertheorie und-optik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena, Germany.
J Phys Chem A. 2007 May 24;111(20):4370-7. doi: 10.1021/jp068294j. Epub 2007 Apr 27.
The electronic and optical properties are studied for three conformers of amino acid molecules using gradient-corrected (spin-) density functional theory within a projector-augmented wave scheme and the supercell method. We investigate single-particle excitations such as ionization energies and electron affinities as well as pair excitations. By comparing eigenvalues resulting from several local and nonlocal energy functionals, the influence of treatment of exchange and correlation is demonstrated. The excitations are described within the Delta-self-consistent field method with an occupation number constraint to obtain excitation energies and Stokes shifts. The results are used to also discuss the optical absorption properties. In contrast to the lowest single- and two-particle excitation energies, remarkable changes are found in absorption spectra in dependence on the conformation of the molecule geometry.
使用投影增强波方法和超胞方法，在梯度校正（自旋）密度泛函理论框架下研究了氨基酸分子三种构象的电子和光学性质。我们研究了单粒子激发，如电离能和电子亲和能以及双粒子激发。通过比较几种局域和非局域能量泛函得到的本征值，证明了交换和关联处理的影响。在具有占据数约束的Delta自洽场方法中描述激发，以获得激发能和斯托克斯位移。这些结果也用于讨论光吸收性质。与最低的单粒子和双粒子激发能不同，发现吸收光谱根据分子几何构象有显著变化。
