What is Marcus Hush theory?
Marcus Hush theory (M-H theory) was developed in 1956 by Rudolph A. Marcus which explains the fundamentals of the redox/ electron transfer reactions in terms of the rate of jumping/moving an electron from oxidant species (electron donor) to the reductant (electron acceptor).
What is the relationship between the free energy change and the reorganization energy when the rate constant is maximal?
2) The maximum rate constant for electron transfer occurs when the free energy is equal and opposite to the reorganization energy. Remember, the free energy for a spontaneous electron transfer is negative and the reorganization energy is positive.
How do you calculate reorganization energy?
The reorganization energy λ is a parameter that contains both inner-sphere (λi) and outer-sphere (λo) components; λ=λi+λo. The inner-sphere reorganization energy is the free-energy change associated with changes in the bond lengths and angles of the reactants.
What is solvent reorganization energy?
The solvent reorganization energy, λ, is the energy required to have solvent molecules in position to solvate the charge-transfer state but without charge-transfer having occurred (see Figure 2). ΔG is the free energy difference between the reactant and charge-transfer states (see Figure 2).
What is reorganization energy?
The reorganisation energy is defined as the energy required to distort the reactant and its associated solvent molecules, from their relaxed nuclear configurations, to the relaxed nuclear configurations of the product and its associated solvent molecules. From: Advances in Physical Organic Chemistry, 2003.
Is nh3 a bridging ligand?
In coordination chemistry, a bridging ligand is a ligand that connects two or more atoms, usually metal ions. The ligand may be atomic or polyatomic….List of bridging ligands.
|N3−||nitride||[Ir 3N(SO 4) 6(H 2O) 3]4−, see metal nitrido complex|
What is a dissociative mechanism?
Dissociative substitution mechanism describes one of the common pathways through which a ligand substitution reaction takes place. This process is analogous to an SN1 reaction. In a dissociative mechanism, the complex is usually has fully saturated coordination, with 18 or more electrons.
How do you find the Marcus cross relation for K12?
(6.25b) α = Δ G 12 ∗ 4 ( Δ G 11 ∗ + Δ G 22 ∗). When the self-exchange rates k 11 are corrected for work terms or when the latter nearly cancel, the cross-reaction rate k 12 is given by the Marcus cross relation, (6.26b) l n f 12 = ( l n K 12) 2 4 l n ( k 11 k 22 ν n 2).
What is the Marcus cross relation for stellacyanin?
Given the measured self-exchange rate constant for stellacyanin (k 11 1.2 x 10 5 M 1 s -1 ), the Marcus cross relation (Equation 6.26a) can be used to calculate the reaction rates for the reduction of Cu II -stellacyanin by Fe (EDTA) 2- and the oxidation of Cu l -stellacyanin by Co (phen) 33+.
What is Marcus theory of reaction rate?
One of the most striking predictions of Marcus theory follows from this equation: as the driving force of the reaction increases, the reaction rate increases, reaching a maximum at – Δ G° = λ; when – Δ G° is greater than λ, the rate decreases as the driving force increases (Figure 6.23).
What are the applications of Marcus theory in chemistry?
Another widely used result of Marcus theory deals with the extraction of useful kinetic relationships for cross reactions from parameters for self-exchange reactions. Consider the cross reaction, Equation (6.22), for which the rate