Term: contact potential difference (Volta potential difference)
https://doi.org/10.1351/goldbook.C01293

Definition:
The electric potential difference between one point in the vacuum close to the surface of M1 and another point in the vacuum close to the surface of M2, where M1 and M2 are two uncharged metals brought into contact.

Related Terms:
1) electric potential (http://doi.org/10.1351/goldbook.E01935).

Source: PAC, 1983, 55, 1251. 'Interphases in systems of conducting phases (Provisional)' on page 1257 (https://doi.org/10.1351/pac198355081251)

Citation: 'contact potential difference (Volta potential difference)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.C01293

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