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  2. Reaction coordinate - Wikipedia

    en.wikipedia.org/wiki/Reaction_coordinate

    In chemistry, a reaction coordinate [1] is an abstract one-dimensional coordinate chosen to represent progress along a reaction pathway. Where possible it is usually a geometric parameter that changes during the conversion of one or more molecular entities, such as bond length or bond angle. For example, in the homolytic dissociation of ...

  3. 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.

  4. C2-Symmetric ligands - Wikipedia

    en.wikipedia.org/wiki/C2-Symmetric_ligands

    Chiral ligands work by asymmetric induction somewhere along the reaction coordinate. The image to the right illustrates how a chiral ligand may induce an enantioselective reaction. The ligand (in green) has C 2 symmetry with its nitrogen, oxygen or phosphorus atoms hugging a central metal atom (in red). In this particular ligand the right side ...

  5. Catalysis - Wikipedia

    en.wikipedia.org/wiki/Catalysis

    An example of heterogeneous catalysis is the reaction of oxygen and hydrogen on the surface of titanium dioxide (TiO 2, or titania) to produce water. Scanning tunneling microscopy showed that the molecules undergo adsorption and dissociation. The dissociated, surface-bound O and H atoms diffuse together.

  6. Transition state - Wikipedia

    en.wikipedia.org/wiki/Transition_state

    The concept of a transition state has been important in many theories of the rates at which chemical reactions occur. This started with the transition state theory (also referred to as the activated complex theory), which was first developed around 1935 by Eyring, Evans and Polanyi, and introduced basic concepts in chemical kinetics that are still used today.

  7. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    Example of an enzyme-catalysed exothermic reaction The relationship between activation energy and enthalpy of reaction (ΔH) with and without a catalyst, plotted against the reaction coordinate. The highest energy position (peak position) represents the transition state.

  8. Catalytic triad - Wikipedia

    en.wikipedia.org/wiki/Catalytic_triad

    A catalytic triad is a set of three coordinated amino acid residues that can be found in the active site of some enzymes. [1] [2] Catalytic triads are most commonly found in hydrolase and transferase enzymes (e.g. proteases, amidases, esterases, acylases, lipases and β-lactamases).

  9. Wilkinson's catalyst - Wikipedia

    en.wikipedia.org/wiki/Wilkinson's_catalyst

    Wilkinson's catalyst is best known for catalyzing the hydrogenation of olefins with molecular hydrogen. [11] [12] The mechanism of this reaction involves the initial dissociation of one or two triphenylphosphine ligands to give 14- or 12-electron complexes, respectively, followed by oxidative addition of H 2 to the metal.