mixed-alkali effect

chemistry

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June 30, 2026

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The mixed-alkali effect is a phenomenon observed in glasses containing two or more different types of alkali ions. When these different alkali ions are present together, the electrical conductivity of the glass is significantly lower than what would be predicted by simply adding the conductivities of each individual alkali ion. This effect is important because alkali ions are the primary charge carriers in glass, and their mobility determines the material's electrical conductivity. The mixed-alkali effect allows for the creation of glasses with lower electrical conductivity, which can be useful in applications like high-wattage lamps.12

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industrial glass
Electrical conductivity
…additivity relationship here is the mixed-alkali effect, in which glasses containing two or more different types of alkali ions have a significantly lower electrical conductivity than linear additivity would suggest. In applications such as high-wattage lamps, where low electrical conductivity is desired, mixed-alkali glasses are useful.
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…additivity relationship here is the mixed-alkali effect, in which glasses containing two or more different types of alkali ions have a significantly lower electrical conductivity than linear additivity would suggest. In applications such as high-wattage lamps, where low electrical conductivity is desired, mixed-alkali glasses are useful.
Read More