The straight line parallel to the direction of chain extension, connecting the centres of mass of successive blocks of chain units, each of which is contained within an identity period.
Source: Purple Book, 1st ed., p. 77 [Terms] [Book]
Citation: 'chain axis' in IUPAC Compendium of Chemical Terminology, 3rd ed. International Union of Pure and Applied Chemistry; 2006. Online version 3.0.1, 2019. https://doi.org/10.1351/goldbook.C00947 RISBibTexEndNote