Results 261 to 270 of about 13,761,270 (353)

Steric effects-II

Tetrahedron, 1980
The steric effect of alkyl groups as characterized by the revised Taft E's parameter is analysed using an approach based on the DARC topological system and its PELCO correlation method. This approach involves an analysis of the systemativ variation of E's in a topological dequencing of alkyl groups and shows the existence of three regions of distinct ...
Annick Panaye, John Anthony MacPhee, Jacques-Emile Dubois   +2 more
openaire   +1 more source

Stabilization of Blue Emitters with Thermally Activated Delayed Fluorescence by the Steric Effect: A Case Study by means of Magnetic Field Effects

, 2020
The use of steric hindrance in blue thermally activated delayed fluorophores shows empirically the improvement of operational lifetime for organic light-emitting diodes (OLEDs).
Chongguang Zhao, Fenggui Zhao, Kai Wang, Haomiao Yu, Tianyu Huang, Rui Wang, Caixia Zhang, Bin Hu, Lian Duan   +8 more
semanticscholar   +1 more source

Attractive steric effects

Journal of Chemical Education, 1973
Attractive steric effects cause some organic structures to be more stable when bulky side-groups are closer together.
A. Liberles, A. Greenberg, J. E. Eilers
openaire   +1 more source

Steric effect on fluorescence quenching

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2005
In this communication we have reported the steric effect on the fluorescence quenching rate constants of the electron transfer (ET) process. We have done a comparative study using donor (D)-acceptor (A) systems with different exergonicity (-deltaG(f)). Different carbazole derivatives (CZ): 1,4-dicyanobenzene (DCB) systems (-deltaG(f) = 0.7-0.8 eV) were
Suchandra, Chatterjee, Samita, Basu, Nandita, Ghosh, Manas, Chakrabarty   +3 more
openaire   +2 more sources

Agostic Interactions in Early Transition-Metal Complexes: Roles of Hyperconjugation, Dispersion, and Steric Effect.

Chemistry, 2019
The agostic interaction is a ubiquitous phenomenon in catalytic processes and transition-metal complexes, and hyperconjugation has been well recognized as its origin.
Xuhui Lin, Wei Wu, Y. Mo
semanticscholar   +1 more source

Steric-hindrance Effect Tuned Ion Solvation Enabling High Performance Aqueous Zinc Ion Batteries.

Angewandte Chemie
Despite many additives have been reported for aqueous zinc ion batteries, steric- hindrance effect of additives and its correlation with Zn2+ solvation structure have been rarely reported. Herein, large-sized sucrose biomolecule is selected as a paradigm
Haozhen Dou, Xinru Wu, Mi Xu, Renwu Feng, Qianyi Ma, Dan Luo, Kai Zong, Xin Wang, Zhongwei Chen   +8 more
semanticscholar   +1 more source

Steric Effect of Protonated Tertiary Amine in Primary-Tertiary Diamine Catalysis: A Double-Layered Sterimol Model.

Organic Letters, 2019
Steric shielding effects are seldom adopted in the stereocontrol with chiral primary amine catalysts. An unexpected steric shielding effect of protonated tertiary amine, a typical hydrogen-bonding moiety, was disclosed.
Yaning Wang, Han-Cheng Zhou, Kai Yang, Chang You, Long Zhang, S. Luo   +5 more
semanticscholar   +1 more source

Steric effects in heteroboranes

Journal of Organometallic Chemistry, 1994
Abstract In (Ph 3 PCu) 2 Ph 2 C 2 B 9 H 9 ( Ia ) and {( o -tol) 3 PCu} 2 Ph 2 C 2 B 9 H 9 ( Ic ) one copper atom occupies a polyhedral vertex position but is slipped away from the cage carbon atoms (the latter the more so) to relieve phosphine ṫ C cage -phenyl crowding. The second copper atom is exo -facially bonded to the B(8)B(9)B(12) triangular
Kerry J. Adams, Jill Cowie, Steven G.D. Henderson, Gillian J. McCormick, Alan J. Welch   +4 more
openaire   +1 more source

Steric effects in dispersion forces interactions

Physical Review E, 2008
Classically, 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, VIRGA, EPIFANIO GUIDO GIOVANNI   +1 more
openaire   +4 more sources

Janus Face of the Steric Effect in a Lewis Acid Catalyst with Size-Exclusion Design: Steric Repulsion and Steric Attraction in the Catalytic Exo-Selective Diels–Alder Reaction

ACS Sustainable Chemistry and Engineering, 2018
An exo-selective catalytic Diels–Alder reaction was developed using a Lewis acid catalyst with size-exclusion structural design. Exploiting the steric effect, especially the steric attraction, the Lewis acid catalyst was able to reroute the reaction ...
Mária Bakos, Zoltán Dobi, Dániel Fegyverneki, Á. Gyömöre, Israel Fernández, T. Soós   +5 more
semanticscholar   +1 more source