Towards efficient ab initio calculations of electron scattering by polyatomic molecules: II. Efficient evaluation of exchange integrals

0347178 - ÚFCH JH 2011 RIV GB eng J - Journal Article
Čársky, Petr
Towards efficient ab initio calculations of electron scattering by polyatomic molecules: II. Efficient evaluation of exchange integrals.
Journal of Physics B-Atomic Molecular and Optical Physics. Roč. 43, č. 17 (2010), s. 175204. ISSN 0953-4075. E-ISSN 1361-6455
R&D Projects: GA MŠMT OC09079; GA MŠMT(CZ) OC10046; GA ČR GA202/08/0631
Institutional research plan: CEZ:AV0Z40400503
Keywords : ab initio calculations * electron scattering * polyatomic molecules
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 1.902, year: 2010

In this paper it is shown that the complex Shavitt functions F-n(z) can be interpolated in the same way as the real Shavitt functions F-n(x) in electronic structure theory. This greatly accelerates the evaluation of exchange integrals in a mixed Gaussian and plane-wave basis. Together with other approximations reported previously this extends applications of ab initio calculations of electron scattering to larger molecules. The performance of the new program was tested for elastic scattering on a training set of eight molecules: H2O, CH4, CF4, ethylene, propane, cyclopropane, benzene and uracil. The vibrational electron energy loss spectra of benzene and uracil were calculated as an example to show that ab initio calculations are now feasible on a desktop computer for molecules of that size.
Permanent Link: http://hdl.handle.net/11104/0188011