Results 251 to 260 of about 7,655,786 (300)

QUANTUM-CHEMICAL CALCULATION OF CHALCON DERIVATIVES

SAKHAROV READINGS 2022: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY Part 2, 2022
The paper presents the data of semi-empirical and theoretical calculations of molecules in the medium of the solvent, their absorption spectrum and the optimized structure with the value of the total energy of the system.
M. A. Atroshko, S. N. Shahab, V. A. Tarasevich, D. A. Martsinkevich, N. V. Bogdanova, W. Hui   +5 more
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Ureases:  Quantum Chemical Calculations on Cluster Models

Journal of the American Chemical Society, 2003
Herein, we present results from a computational study of dinickel complexes that are relevant to the catalytic hydrolysis of urea exerted by the urease enzymes. The B3LYP density functional is used to characterize the equilibrium geometry, electronic and magnetic properties, and energies for a series of realistic complexes modeling the active site of ...
Dimas, Suárez, Natalia, Díaz, Kenneth M, Merz   +2 more
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Semiempirical quantum chemical calculations of molecular ?- complexes

Theoretica Chimica Acta, 1980
A method is suggested to calculate the geometrical and thermodynamical characteristics of organic π- complexes. The interaction energy is considered as a sum of two terms: the specific quantum chemical interaction of the π- electron systems depending essentially on the chemical nature of reactants, and the nonspecific atom-atom (van-der-Waals ...
Michael V. Basilevsky, Noham N. Weinberg, Victor M. Zhulin   +2 more
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NMR spectroscopy: quantum‐chemical calculations

WIREs Computational Molecular Science, 2011
AbstractThe first‐principles computation of nuclear magnetic resonance parameters, in particular chemical shift and spin–spin coupling tensors, is reviewed. After a brief nontechnical introduction into the methodology behind such calculations, selected applications from chemistry and biochemistry in solution and the solid state are highlighted. Special
Michael Bühl, Tanja van Mourik
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QUANTUM-CHEMICAL CALCULATION OF PYRIMIDINE BASES

SAKHAROV READINGS 2022: ENVIRONMENTAL PROBLEMS OF THE XXI CENTURY Part 2, 2022
The paper presents the data of semi-empirical and theoretical calculations of molecules in the medium of the solvent, their absorption spectrum and the optimized structure with the value of the total energy of the system.
M. A. Atroshko, S. N. Shahab, J. V. Ignatovich, N. V. Bogdanova, Y. Shu, W. Hui   +5 more
openaire   +1 more source

Quantum Chemical Calculations of Sulfur‐Rich Compounds

ChemInform, 2004
AbstractFor Abstract see ChemInform Abstract in Full Text.
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Quantum-chemical and statistical calculations on phospholipids

Chemistry and Physics of Lipids, 1982
Abstract Using empirical potential functions quasi-statistical conformational calculations have been performed on phosphatidylethanolamine (PE) and phosphatidylcholine (PC) head groups. For both systems the main component of the dipole moment (about 20 D) lies within the plane of the monolayer, while the normal component (about −5 D) is smaller and ...
Horst Frischleder, Gustav Peinel
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Quantum chemical definition and calculation of valence

Journal of Molecular Structure: THEOCHEM, 1993
Abstract A new quantum chemical definition of atomic valence is proposed by taking into account both the final and initial states of atoms forming molecules. For the practical calculation, we present a corresponding concrete calculation procedure within the framework of the maximum overlap population principle, which is very simple and very easy to ...
Guang-Xian Xu, Chang-Guo Zhan
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Quantum chemical calculations on the ‘macrocyclic effect’

Inorganica Chimica Acta, 1983
Abstract Quantum chemical calculations within the framework of the HF-LCAO-MO method have been performed in order to obtain insight into the nature of the well-known ‘Macrocyclic Effect’. The results indicate the effect to be mainly due to the fact that the cyclic ligands are already ‘pre-strained’, i.e.
G.J. Reibnegger, B.M. Rode
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A Quantum Chemical Calculation of the C6H Radical

Publications of the Astronomical Society of Japan, 1987
Abstract The molecular structure of the C6H radical was studied by the abinitio SCF method with the MIDI-4 basis set. Contrary to small even carbon-chains C2H and C4H, whose ground states are 2 Σ +, the electronic ground state of the C6H radical is likely to be 2Π, although the calculated energy difference between the 2Π state and 2Π ...
Akinori Murakami, Kentarou Kawaguchi, Shuji Saito   +2 more
openaire   +1 more source