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Steric effects in dispersion forces interactions
Physical Review E, 2008Classically, there have been two different ways to obtain mean-field theories for liquid crystals. One is based on short-range repulsive steric forces and the other on long-range attractive dispersion forces. In the former approach, it is the anisotropic shape of the molecules that leads to the anisotropic interaction, and in the latter it is the ...
SONNET A. M +1 more
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Remote Control by Steric Effects
Science, 2014A rhodium-catalyzed reaction places a silicon substituent on the site farthest away from the largest group present on an aromatic ring. [Also see Research Article by Cheng and Hartwig ]
Naoto Chatani, Mamoru Tobisu
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Fisher information and steric effect
Chemical Physics Letters, 2007Abstract A modified Fisher information, the sum of the one-electron Fisher information, is proposed. It is shown that the modified Fisher information is the original Fisher information plus a sum of differences of quantum and classical variances. A generalization of the Stam’s inequality is derived.
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Steric effects in carbene cycloadditions
Tetrahedron Letters, 1983Abstract Steric effects in cycloadditions with alkenes prevent the occurrence of a general linear free energy relationship between the reactivities of carbenes. Nevertheless, the isoselective temperature remains constant.
Bernd Giese, Woo Bung Lee, Carola Stiehl
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Steric effects on atropisomerism in tetraarylporphyrins
Journal of the American Chemical Society, 1987AbstractThe rate of aryl ring rotation in the series of porphyrins (I) is studied by NMR spectroscopy and chromatography.
Leslie D. Field +4 more
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Sterically crowded aryloxide compounds of aluminum: electronic and steric effects
Organometallics, 1991The mononuclear, four-coordinate aluminum compounds AlR 2 (BHT)L and AlR(BHT) 2 L [R=Me, Et; BHT=2,6-di-tert-butyl-4-methylphenoxide; L=2-Mepy, 4-Mepy, 2,6-Me 2 py, CH 3 CN, N(C 2 H 4 ) 3 CH, HNEt 2 , HN i Bu 2 , H 2 N t Bu,H 2 N n Bu, NH 3 , py•O] are obtained when AlR 3 is treated with the correct molar equivalent of BHT-H and the appropriate Lewis ...
Matthew D. Healy +2 more
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The question of remote steric effects
Tetrahedron Letters, 1994Abstract Remote steric effects, thought to arise from long hydrocarbon chains coiling about reactive sites, are absent in three non-aqueous systems designed to maximize the effect.
F.M. Menger, Kingsley H. Nelson
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Steric effects on geminate recombinations
Journal of the American Chemical Society, 1990Steric effects on the binding of isonitrile ligands to iron(II) porphyrins were investigated by picosecond flash photolysis. Two different types of steric effects were distinguished and characterized: (1) steric restrictions to porphyrin planarity and (2) blocking of the pathway for ligand approach.
Douglas Magde +3 more
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Is the Hammett’s Constant Free of Steric Effects?
The Journal of Physical Chemistry A, 2012In this work, we have explored the validity of the hypotheses on which rest the Hammett's approach to quantify the substituent effect on a reaction center, by applying two DFT energy decomposition schemes. This is performed by studying the change in the total electronic energy, ΔΔE, associated with a proton transfer isodesmic equilibrium.
Luis Rincón, Rafael Almeida
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Steric effects in hydrosilylation of styrene
Collection of Czechoslovak Chemical Communications, 1980Hydrosilylation of styrene, 2-phenyl-1-propene, trans-1-phenyl-1-propene by (CH3)R2SiH (R = C2H5, i-C3H7, i-C4H9) and R'3SiH (R' = i-C3H7, t-C4H9) in the presence of [RhCl.{P(C6H5)3}3] (I), [{RhCl(C2H4)2}2] (II) and H2PtCl6 as catalysts has been studied.
Gabriela Kuncová, Václav Chvalovský
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