Results 251 to 260 of about 1,493,686 (274)

Low-field 3-DFT MRI: Conceptual, Analytical And Experimental Aspects

1990 IEEE Nuclear Science Symposium Conference Record, 1991
Three-dimensional Fourier transform (3-DFT) magnetic resonance imaging (MRI) offers advantages in terms of signal-to-noise (S/N) per unit of time for the case where a large number of slices is desired. This advantage is enhanced when the relaxation time, T(1 ), is short.
D M, Kramer, L, Kaufman, P, Rothschild, J, Hale, J, Wummer, K K, Hake   +5 more
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On the link between the reaction force constant and conceptual DFT

Journal of Molecular Modeling
The reaction force constant ( κ ), introduced by Professor Alejandro Toro-Labbé, plays a pivotal role in characterizing the reaction pathway by assessing the curvature of the potential energy profile along the intrinsic reaction coordinate. This study establishes a novel link between κ and the reactivity descriptors of conceptual density functional ...
Carlos, Cárdenas, Paul W, Ayers, Debajit, Chakraborty, Tatiana, Gómez, Andrea, Echeverri, Francisco, Munoz, Patricio, Fuentealba   +6 more
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Atomic decomposition of conceptual DFT descriptors: application to proton transfer reactions

Physical Chemistry Chemical Physics, 2015
We present an atomic decomposition of the molecular energy, reaction force and reaction flux, which is based on Bader's atoms-in-molecules theory.
Inostroza-Rivera, R., Yahia-Ouahmed, Meziane, Tognetti, Vincent, Joubert, Laurent, Herrera, B., Toro-Labbé, A.   +5 more
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Interpretation of Hydrogen Bonding in the Weak and Strong Regions Using Conceptual DFT Descriptors [PDF]

The Journal of Physical Chemistry A, 2006
Hydrogen bonding is among the most fundamental interactions in biology and chemistry, providing an extra stabilization of 1-40 kcal/mol to the molecular systems involved. This wide range of stabilization energy underlines the need for a general and comprehensive theory that will explain the formation of hydrogen bonds.
Özen, Alimet Sema, Proft, Frank De, Aviyente, Viktorya, Geerlings, Paul   +3 more
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Structural variation facilitate alkylation: A conceptual DFT study

Computational and Theoretical Chemistry, 2012
In this paper, the variation of the DFT-based reactivity descriptors, such as chemical potential, chemical hardness, electrophilicity, Fukui function and local electrophilicity, for a family of anticancer drug intermediate have been analyzed. Based on our findings, we suggest that structural variation in the drug intermediate assist alkylation of DNA ...
Babul Neog, Nabajit Sarmah, Rahul Kar, Pradip Kr. Bhattacharyya   +3 more
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ChemInform Abstract: Conceptual and Computational DFT in the Study of Aromaticity

ChemInform, 2001
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Frank De Proft, Paul Geerlings
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Structure–activity relations of 2-(methylthio)benzimidazole by FTIR, FT-Raman, NMR, DFT and conceptual DFT methods

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2014
The vibrational fundamental modes of 2-(methylthio)benzimidazole (2MTBI) have been analysed by combining FTIR, FT-Raman and quantum chemical calculations. The structural parameters of the compound are determined from the optimised geometry by B3LYP with 6-31G(∗∗), 6-311++G(∗∗) and cc-pVTZ basis sets and giving energies, harmonic vibrational frequencies,
V, Arjunan, Arushma, Raj, P, Ravindran, S, Mohan   +3 more
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A New View on the Spectrochemical and Nephelauxetic Series on the Basis of Spin‐Polarized Conceptual DFT

ChemPhysChem, 2009
AbstractIn a row: Chemical concepts from the spin‐polarized conceptual DFT field are used to explain the spectrochemical and nephelauxetic series within a group of ruthenium complexes.magnified imageThe spectrochemical and nephelauxetic series are analyzed within the context of spin‐polarized conceptual DFT. For a series of different [RuL6]x complexes,
Moens, Jan, Jaque Olmedo Pablo, Cesar, De Proft, Frank, Geerlings, Paul   +3 more
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Na N + (N ⩽ 12) clusters fragmentation channels: A conceptual DFT approach

Journal of Computational Methods in Sciences and Engineering, 2008
In this paper we study the small Na N + (N ⩽ 12) cationic clusters fragmentation channels, with all electronic calculations performed at the B3LYP/6–311G+(d,p) DFT level of theory. For these cluster sizes, we obtain for all neutral, cationic, bi-cationic and anionic species the optimized geometries, total energies and electronic properties such as the ...
Gregorio Guzmán-Ramírez, Agustín Segovia-Ríos, Jorge Sierra-Arellano, Juvencio Robles   +3 more
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DFT and conceptual-DFT assessment on selective tertiary amine functionalized calix[4]arene-anion interaction

Computational and Theoretical Chemistry, 2017
Abstract In this paper, previously reported selectivity of a tetraamine-substituted calix[4]arene receptor (CX4) towards four biologically and environmentally relevant anions has been tried to be supported by two separate computational studies, of which the former is based on thermodynamical approach and the second is on the calculation of reactivity
SAYIN, SERKAN, DEMİR, SERKAN, ENGİN, MEHMET SONER, ÇAY, SEYDAHMET, Eymur, Serkan, Koseoglu, Tugba Sardohan   +5 more
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