Term: metal–insulator transition
https://doi.org/10.1351/goldbook.M03863

Definition:
A transition characterized by a sudden change in electrical transport properties (conductivity) due to a reversible change from localized to itinerant behaviour of the electrons. Example: The transition at 339 K in VO2 where it changes from a high-temperature metallic behaviour to a low-temperature semiconductor behaviour. Synonymous with metal–nonmetal transition.

Related Terms:
1) semiconductor (http://doi.org/10.1351/goldbook.S05591).
2) localized-itinerant transition (http://doi.org/10.1351/goldbook.L03608).

Source: PAC, 1994, 66, 577. 'Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)' on page 586 (https://doi.org/10.1351/pac199466030577)

Citation: 'metal–insulator transition' 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.M03863

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