Term: mesomorphic state
https://doi.org/10.1351/goldbook.MT06853

Definition:
A state of matter in which the degree of molecular order is intermediate between the perfect three-dimensional, long-range positional and orientational order found in solid crystals and the absence of long-range order found in isotropic liquids, gases, and amorphous solids.

Related Terms:
1) isotropic (http://doi.org/10.1351/goldbook.I03353).

Source: PAC, 2002, 74, 493. 'Definitions of basic terms relating to polymer liquid crystals (IUPAC Recommendations 2001)' on page 495 (https://doi.org/10.1351/pac200274030493)

Citation: 'mesomorphic state' 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.MT06853

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