Results 271 to 280 of about 166,181 (310)

DFT Calculation of the Solid Acidity

2010
Density functional theory (DFT) is applied to calculate the ammonia desorption energies on zeolites with various framework types and Y zeolites with various exchange cations. The calculated desorption energy is in good agreement with the ammonia IRMS-TPD measurements. Relationships between the acid strength and geometric parameters are found.
Miki Niwa, Naonobu Katada, Kazu Okumura
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An approach to DFT calculations using standard microprocessors

IBM Journal of Research and Development, 1985
The use of the DFT as an everyday tool is now commonplace, principally due to advances in hardware technology. Special-purpose VLSI chips for signal processing are available. In this paper, we describe an approach which marries the Winograd Fourier Transform Algorithm (WFTA) with a state-of-the-art 16-bit general-purpose microprocessor for the purpose ...
James T. Rayfield, Harvey F. Silverman
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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.
M, Wolniak, I, Wawer
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On the position of the potential wall in DFT temporary anion calculations

Physical Chemistry Chemical Physics, 2007
A simple method was recently proposed [D. J. Tozer and F. De Proft, J. Chem. Phys., 2007, 127, 034108] for performing explicit density functional theory (DFT) calculations on temporary anions. The excess electron in the anion is bound by a potential wall, the position of which is determined by a single parameter lambda, chosen to reproduce an ...
Sablon, Nick, De Proft, Frank, Geerlings, Paul, Tozer, D.j.   +3 more
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Assessing calculated DFT properties

Science, 2014
Catalysis Density functional theory (DFT) is now widely used to calculate molecular and material properties. DFT's reliability is usually assessed by comparison with experimental values and higher-level theoretical methods. Medford et al. used the BEEF-vdW, an exchange-correlation density functional tailored for surface chemistry, and looked at ...
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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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Vibrational spectra and DFT calculations of squalene

Journal of Molecular Structure, 2013
Abstract The isoprenoid compound squalene is a building block molecule for the production of essential cellular molecules such as membrane sterols, has several therapeutic activities including anticancer properties, and has commercial applications for a variety of industries including the production of cosmetics.
Hye Jin Chun, Taylor L. Weiss, Timothy P. Devarenne, Jaan Laane   +3 more
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DFT Calculations of a Metal-TCNE Complex

AIP Conference Proceedings, 2007
For V[TCNE](x) y(solvent) (TCNE = tetracyanoethylene), the first room-temperature molecular magnet, the mechanism for the strong exchange coupling in the family M[TCNE](x) y(solvent) has remained a ...
Corneliu I. Oprea, Alina Damian, Mihai A. Gîrţu   +2 more
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DFT Calculation of Glycine with Methanols Clusters

Chinese Journal of Chemical Physics, 2009
Density functional theory (DFT) calculations are reported for the structures of neutral and zwitterionic glycine-(CH3OH)n where n = 16. Initial geometries of the clusters of neutral and zwitterionic glycine with 16 methanol molecules are fully optimized at B3LYP/631+G* level of theory.
Hao Zou, Yong-jun Hu, Da Xing
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DFT CALCULATIONS OF BENZOISOXAZOLE DERIVATIVES

2019
In this work, we carried out theoretical calculations to determine the structureactivity relationship and the properties of two benzoisoxazole derivatives. For the quantum chemical calculations, the Density Functional Theory (DFT) with B3LYP (Becke threeparameter hybrid correlation functional combined with Lee–Yang–Parr correlation functional) and 6 ...
ÖZEN, Ezgi, KALKAN, Melike, ÜNAL CİVCİR, Pervin   +2 more
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