14220 IUPAC Gold Book - frustration 10.1351/goldbook.14220 14220 current 1 Feature of crystalline packing characterized by different crystalline arrangements of chain stems at two (or more) sites that would be expected to be equivalent. The term "frustration" signifies that some chains can achieve the minimum energycconformation or an optimal packing arrangement, while others cannot. A crystalline polymer structure exhibiting frustration is the \(\ce{\upbeta\mbox{-}polymorph}\) of isotactic polypropylene. PAC, 2011, 83, 1831. 'Definitions of terms relating to crystalline polymers (IUPAC Recommendations 2011)' on page 1845 (https://doi.org/10.1351/PAC-REC-10-11-13) https://goldbook.iupac.org/terms/view/14220/html https://goldbook.iupac.org/terms/view/14220/json https://goldbook.iupac.org/terms/view/14220/plain Citation: 'frustration' 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.14220 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. 2026-06-29T00:34:02+00:00