## Weller correlation

https://doi.org/10.1351/goldbook.W06671
Empirical correlation for the energy of full charge-transfer @[email protected] relative to the @[email protected] in n-hexane as a function of the electrochemical one electron standard reduction potential of the @[email protected] produced upon electron donation and standard reduction potential of the acceptor measured in a @[email protected] for the donor (D) and the acceptor (A) involved $\Delta H(\text{D}^{+}\text{A}^{-},\text{hexane}) = e\left [ E^{0}(\text{D}^{+\bullet }/\text{D}) - E^{0}(\text{A}/\text{A}^{-\bullet }) \right ]+e\Delta E$ with $$E^{0}(D^{+\bullet }/D)$$ and $$E^{0}(A/D^{-\bullet })$$ the standard electrode potentials of the donor and acceptor, respectively.
Notes:
1. In the case diethylaniline as donor and aromatic @[email protected] as acceptors, the last term on the right, i.e., $$e\Delta E = (0.15 \pm 0.10)\ \text{eV}$$. This equation assumes a constant @[email protected] term and a constant @[email protected] change within a particular series of partners. $$e$$ is the @[email protected]
2. The IUPAC recommendations for the sign and symbols of standard potentials are used in the equation as written above.
3. Although not complying with the IUPAC recommended nomenclature for the standard electrode potentials, traditionally the equation has been written as: $\Delta H(\text{D}^{+}\text{A}^{-},\text{hexane}) = e\left [ E_{\text{ox}}^{0} - E_{\text{red}}^{0} \right ]+(0.15 \pm 0.10)\ \text{eV}$ with $$E_{\text{ox}}^{0}$$ the @[email protected] at which the @[email protected] occurs, and $$E_{\text{red}}^{0}$$ the @[email protected] at which the reduction occurs. This writing of the first term within the square brackets is misleading and not recommended.
Source:
PAC, 2007, 79, 293. (Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)) on page 439 [Terms] [Paper]