Results 11 to 20 of about 119,298 (312)
Steric effects in cyclization reactions [PDF]
Australian Journal of Chemistry, 1976 Calculations of geometric probability factors indicate that steric effects are important in determining whether the cyclization of β-substituted diallylmethylammonium ions results in five- or six-memberedrings. Evidence is obtained of the direction of intramolecular attack.
David H. Solomon +3 more
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In silico geometric and energetic data of all possible simple rotamers made of non-metal elements
Data in Brief, 2020 This article presents theoretical data on geometric and energetic features of halogenated rotamers of the following backbone structures, CC, NN, PP, OO, SS, NP, OS, CN, CP, CO, CS, NO, NS, PO and PS.
Taweetham Limpanuparb +3 more
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Steric Effects on Electroosmotic Nano-Thrusters under High Zeta Potentials
Mathematics, 2021 Here, space electroosmotic thrusters in a rigid nanochannel with high wall zeta potentials are investigated numerically, for the first time, considering the effect of finite size of the ionic species. The effect, which is called a steric effect, is often
Jiaxuan Zheng, Siyi An, Yongjun Jian
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Hypervariability of accessible and inaccessible conformational space of proteins
Current Research in Structural Biology, 2021 Proteins undergo motions in a range of amplitudes, from domain motions to backbone rotations, leading to changes in (φ,ψ) torsion angles and small-scale bond vibrations and angle bending.
Ashraya Ravikumar +1 more
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Molecules, 2001 Benzonorbornadiene 21, 7-spirocyclopropylbenzonorbornadiene 23, 7,7-dimethylbenzonorbornadiene 25, and 7-spirocyclopentylbenzonorbornadiene 27 have been reacted with 3,6-di(2-pyridyl)-s-tetrazine (rate: 21>23>25=27) to form symmetrical 4,5 ...
Peter A. Harrison, Ronald N. Warrener
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El Niño, La Niña, and the global sea level budget [PDF]
Ocean Science, 2016 Previous studies show that nonseasonal variations in global-mean sea level (GMSL) are significantly correlated with El Niño–Southern Oscillation (ENSO).
C. G. Piecuch, K. J. Quinn
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ChemistryOpen, 2019 A computational analysis of a series of cationic and neutral gold imidazolylidene and benzimidizolylidene complexes is reported. The Bond Dissociation Energies of the various ligands in the complexes calculated at the PBE0‐D3/def2‐TZVP level of theory ...
Sunel de Kock +2 more
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Kinetics of the reaction of 5-substituted orotic acids with diazodiphenylmethane [PDF]
Journal of the Serbian Chemical Society, 2004 Rate konstants for the reaction of eight 5-substituted orotic acids with diazodiphenylmethane (DDM) in dimethylformamide (DMF) were determined at 30 ºC by the known spectrophotometric method.
ALEKSANDAR D. MARINKOVIC +2 more
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Does the Intra‐Atomic Deformation Energy of Interacting Quantum Atoms Represent Steric Energy?
ChemistryOpen, 2019 We show that the mutual, through‐space compression of atomic volume experienced by approaching topological atoms causes an exponential increase in the intra‐atomic energy of those atoms, regardless of approach orientation. This insight was obtained using
Benjamin C. B. Symons +4 more
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Density Functional Studies on Secondary Amides: Role of Steric Factors in Cis/Trans Isomerization
Molecules, 2018 Cis/trans isomerization of amide bonds is a key step in a wide range of biological and synthetic processes. Occurring through C-N amide bond rotation, it also coincides with the activation of amides in enzymatic hydrolysis.
Balmukund S. Thakkar +2 more
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