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  2. Rotamer - Wikipedia

    en.wikipedia.org/wiki/Rotamer

    The two have equal free energy; neither is more stable, so neither predominates compared to the other. A negative difference in free energy means that a conformer interconverts to a thermodynamically more stable conformation, thus the equilibrium constant will always be greater than 1.

  3. Gauche effect - Wikipedia

    en.wikipedia.org/wiki/Gauche_effect

    The gauche effect is very sensitive to solvent effects, due to the large difference in polarity between the two conformers.For example, 2,3-dinitro-2,3-dimethylbutane, which in the solid state exists only in the gauche conformation, prefers the gauche conformer in benzene solution by a ratio of 79:21, but in carbon tetrachloride, it prefers the anti conformer by a ratio of 58:42. [9]

  4. Curtin–Hammett principle - Wikipedia

    en.wikipedia.org/wiki/Curtin–Hammett_principle

    The Curtin–Hammett principle is a principle in chemical kinetics proposed by David Yarrow Curtin and Louis Plack Hammett.It states that, for a reaction that has a pair of reactive intermediates or reactants that interconvert rapidly (as is usually the case for conformational isomers), each going irreversibly to a different product, the product ratio will depend both on the difference in ...

  5. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    The remainder of them were product molecules in the immediate past ([AB r] ‡). In TST, it is assumed that the flux of activated complexes in the two directions are independent of each other. That is, if all the product molecules were suddenly removed from the reaction system, the flow of [AB r] ‡ stops, but there is still a flow from left ...

  6. Chemical stability - Wikipedia

    en.wikipedia.org/wiki/Chemical_stability

    In chemistry, chemical stability is the thermodynamic stability of a chemical system, in particular a chemical compound or a polymer. [1] Colloquially, it may instead refer to kinetic persistence, the shelf-life of a metastable substance or system; that is, the timescale over which it begins to degrade.

  7. Decalin - Wikipedia

    en.wikipedia.org/wiki/Decalin

    The trans form is energetically more stable because of fewer steric interactions. cis-Decalin is a chiral molecule without a chiral center; it has a two-fold rotational symmetry axis, but no reflective symmetry. However, the chirality is canceled through a chair-flipping process that turns the molecule into its mirror image.

  8. Cyclohexane conformation - Wikipedia

    en.wikipedia.org/wiki/Cyclohexane_conformation

    Cyclohexane is the most stable of the cycloalkanes, due to the stability of adapting to its chair conformer. [4] This conformer stability allows cyclohexane to be used as a standard in lab analyses. More specifically, cyclohexane is used as a standard for pharmaceutical reference in solvent analysis of pharmaceutical compounds and raw materials.

  9. Cyclooctatetraene - Wikipedia

    en.wikipedia.org/wiki/Cyclooctatetraene

    In its normal state, cyclooctatetraene is non-planar and adopts a tub conformation with angles C=C−C = 126.1° and C=C−H = 117.6°. [10] The point group of cyclooctatetraene is D 2d. [11] In its planar transition state, the D 4h transitional state is more stable than the D 8h transitional state due to the Jahn–Teller effect. [12]