Results 211 to 220 of about 297,991 (240)

MP2, DFT and ab initio calculations on thioxanthone

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2011
Density functional theory (DFT), HF and MP2 calculations have been carried out to investigate thioxanthone molecule using the standard 6-31+G(d,p) basis set. The results of MP2 calculations show a butterfly structure for thioxanthone. The calculated results show that the predicted geometry can well reproduce the structural parameters.
Alireza Salimi Beni, Alireza Najafi Chermahini, Hashem Sharghi, Setareh Mirzaei Monfared   +3 more
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DFT and HF–DFT calculations of quadrupole coupling constants in molecules

Chemical Physics, 2000
Abstract The efficacy of several DFT and HF–DFT methods for the calculation of 14 N quadrupole coupling constants in molecules has been investigated. Valence triple-zeta quality Pople and Dunning correlation consistent type bases were used.
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13C CPMAS NMR and DFT calculations of anthocyanidins

Solid State Nuclear Magnetic Resonance, 2008
Anthocyanidins, red dyes from flower petals and fruits, are beneficial to human health. They attract considerable attention owing to their strong antioxidant and radical scavenging properties, however they are unstable in solution and available in small amounts only.
Michał Wolniak, Iwona Wawer
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Improved DFT calculation of Raman spectra of silicates

Vibrational Spectroscopy, 2011
Abstract Very accurate vibrational spectra of silicates are obtained from DFT calculations if the appropriate Hamiltonian is used. Theoretical considerations suggest that the Hartree–Fock component of ACM1 hybrid functionals should be 1/6 instead of 1/4 for this class of compounds.
Volker Kahlenberg, Daniel M. Többens
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DFT calculations of solids with LAPW and WIEN2k

Journal of Solid State Chemistry, 2003
Abstract In solids one often starts with an ideal crystal that is studied on the atomic scale at zero temperature. The unit cell may contain several atoms (at certain positions) and is repeated with periodic boundary conditions. Quantum mechanics governs the electronic structure that is responsible for properties such as relative stability, chemical ...
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Lithium Storage on Graphdiyne Predicted by DFT Calculations

The Journal of Physical Chemistry C, 2012
Graphdiyne (GD) is a new carbon allotrope, consisting of an sp- and sp2-hybridized carbon network. In this work, density functional theory calculations are carried out to investigate the adsorption and diffusion of lithium (Li) atoms on GD monolayers, and the results are compared with those for graphyne and graphene monolayers. High-capacity Li storage,
Sun, Chenghua, Searles, Debra J.
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Excitation energy calculations with TD-DFT

2005
Der rechnerische Aufwand von quantenmechanischen Berechnungen der Materiestruktur skaliert mit der Potenz der berucksichtigten Teilchen. Die Dichtefunktionaltheorie (DFT) benutzt als grundlegende Variable die elektronische Dichte statt der Wellenfunktion, was die Anzahl der Freiheitsgrade auf drei beschrankt.
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Fast Algorithms For Calculating The Dft

IEEE South African Symposium on Communications and Signal Processing, 2005
H.C. Kotze, J.J.D. van Schalkwyk
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DFT CALCULATIONS OF COPPER CLUSTERS

Physics, Chemistry and Application of Nanostructures, 2003
Oleg A. Ivashkevich, Vitaly E. Matulis
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Mixed-Basis Scheme for DFT Calculations

1995
A combined basis consisting of core orbitals, in a special way localized valence orbitals, and orthogonalized (to core orbitals only) plane waves is introduced for variational solutions of Kohn-Sham equations. The localized orbitals represent atomic valence orbitals in the range of their radial nodes with high precision, but are smoothly compressed in ...
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