06853 IUPAC Gold Book - mesomorphic state 10.1351/goldbook.MT06853 MT06853 current 1 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. isotropic https://goldbook.iupac.org//terms/view/I03353 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) https://goldbook.iupac.org/terms/view/MT06853/html https://goldbook.iupac.org/terms/view/MT06853/json https://goldbook.iupac.org/terms/view/MT06853/plain 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. 10.1351/goldbook.MT06853 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-04-19T04:23:47+00:00