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  2. Transition state - Wikipedia

    en.wikipedia.org/wiki/Transition_state

    In chemistry, the transition state of a chemical reaction is a particular configuration along the reaction coordinate. It is defined as the state corresponding to the highest potential energy along this reaction coordinate. [1] It is often marked with the double dagger (‡) symbol.

  3. Activated complex - Wikipedia

    en.wikipedia.org/wiki/Activated_complex

    The transition state, represented by the double dagger symbol represents the exact configuration of atoms that has an equal probability of forming either the reactants or products of the given reaction. [5] The activation energy is the minimum amount of energy to initiate a chemical reaction and form the activated complex. [6]

  4. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    All chemical transformations pass through an unstable structure called the transition state, which is poised between the chemical structures of the substrates and products. The transition states for chemical reactions are proposed to have lifetimes near 10 −13 seconds, on the order of the time of a single bond vibration.

  5. Reaction coordinate - Wikipedia

    en.wikipedia.org/wiki/Reaction_coordinate

    In the formalism of transition-state theory the reaction coordinate for each reaction step is one of a set of curvilinear coordinates obtained from the conventional coordinates for the reactants, and leads smoothly among configurations, from reactants to products via the transition state. It is typically chosen to follow the path defined by ...

  6. Hammond's postulate - Wikipedia

    en.wikipedia.org/wiki/Hammond's_postulate

    George Hammond developed the postulate during his professorship at Iowa State University. Hammond's postulate (or alternatively the Hammond–Leffler postulate), is a hypothesis in physical organic chemistry which describes the geometric structure of the transition state in an organic chemical reaction. [1]

  7. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    A chemical reaction is able to manufacture a high-energy transition state molecule more readily when there is a stabilizing fit within the active site of a catalyst. The binding energy of a reaction is this energy released when favorable interactions between substrate and catalyst occur. The binding energy released assists in achieving the ...

  8. Cope rearrangement - Wikipedia

    en.wikipedia.org/wiki/Cope_rearrangement

    The transition state of the molecule passes through a boat or chair like transition state. An example of the Cope rearrangement is the expansion of a cyclobutane ring to a cycloocta-1,5-diene ring: In this case, the reaction must pass through the boat transition state to produce the two cis double bonds.

  9. SN2 reaction - Wikipedia

    en.wikipedia.org/wiki/SN2_reaction

    The formation of the C–Nu bond, due to attack by the nucleophile (denoted Nu), occurs together with the breakage of the C–X bond. The reaction occurs through a transition state in which the reaction center is pentacoordinate and approximately sp 2-hybridised.