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  2. Activation strain model - Wikipedia

    en.wikipedia.org/wiki/Activation_strain_model

    The activation strain model was originally proposed and has been extensively developed by Bickelhaupt and coworkers. [4] This model breaks the potential energy curve as a function of reaction coordinate, ζ, of a reaction into 2 components as shown in equation 1: the energy due to straining the original reactant molecules (∆E strain) and the energy due to interaction between reactant ...

  3. Hammond's postulate - Wikipedia

    en.wikipedia.org/wiki/Hammond's_postulate

    In an E2 mechanism, a base takes a proton near the leaving group, forcing the electrons down to make a double bond, and forcing off the leaving group-all in one concerted step. The rate law depends on the first order concentration of two reactants, making it a 2nd order (bimolecular) elimination reaction.

  4. Elimination reaction - Wikipedia

    en.wikipedia.org/wiki/Elimination_reaction

    Elimination reaction of cyclohexanol to cyclohexene with sulfuric acid and heat [1] An elimination reaction is a type of organic reaction in which two substituents are removed from a molecule in either a one- or two-step mechanism. [2] The one-step mechanism is known as the E2 reaction, and the two-step mechanism is known as the E1 reaction ...

  5. Linnett double-quartet theory - Wikipedia

    en.wikipedia.org/wiki/Linnett_Double-Quartet_Theory

    Much like Lewis’ bonding model, LDQ theory assumes that the dominant contributions result from electron-electron and electron-nuclear interactions. [20] However, it has previously been shown that the introduction of nuclear-nuclear interactions into LDQ theory can explain some trends in bond angles and bond lengths . [ 20 ]

  6. Marcus theory - Wikipedia

    en.wikipedia.org/wiki/Marcus_theory

    In outer sphere redox reactions no bonds are formed or broken; only an electron transfer (ET) takes place. A quite simple example is the Fe 2+ /Fe 3+ redox reaction, the self exchange reaction which is known to be always occurring in an aqueous solution containing the aquo complexes [Fe(H 2 O) 6] 2+ and [Fe(H 2 O)6] 3+.

  7. Energy profile (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Energy_profile_(chemistry)

    Figure 6:Reaction Coordinate Diagrams showing reactions with 0, 1 and 2 intermediates: The double-headed arrow shows the first, second and third step in each reaction coordinate diagram. In all three of these reactions the first step is the slow step because the activation energy from the reactants to the transition state is the highest.

  8. Reactivity series - Wikipedia

    en.wikipedia.org/wiki/Reactivity_series

    The order of reactivity, as shown by the vigour of the reaction with water or the speed at which the metal surface tarnishes in air, appears to be Cs > K > Na > Li > alkaline earth metals, i.e., alkali metals > alkaline earth metals, the same as the reverse order of the (gas-phase) ionization energies.

  9. Zeldovich–Liñán model - Wikipedia

    en.wikipedia.org/wiki/Zeldovich–Liñán_model

    The model includes a chain-branching and a chain-breaking (or radical recombination) reaction. The model was first introduced by Zeldovich in 1948 [1] and later analysed by Liñán using activation energy asymptotics in 1971. [2] The mechanism with a quadratic or second-order recombination that were originally studied reads as