Short range order

{{short description|When crystalline ordering in a solid only extends a short distance}}

In crystallography, short range order refers to the regular and predictable arrangement (i.e. crystalline lattice) of atoms over a short distance, usually with one or two atom spacings. However, this regularity described by short-range order does not necessarily apply to a larger area.{{Cite book|url=https://books.google.com/books?id=sBhZnPPgt90C&q=short+range+order+chemistry&pg=PA2|title=The Physics and Chemistry of Nanosolids|last1=Owens|first1=Frank J.|last2=Poole|first2=Charles P. Jr.|author2-link=Charles P. Poole|date=2008-04-11|publisher=John Wiley & Sons|isbn=9780470067406|language=en}} Examples of materials with short range order include amorphous materials such as wax, glass and liquids{{Cite web|url=https://www.slideshare.net/mobile/anshulbehappy/crystalography-33018315|title = Crystalography|date = April 2014}} as well as the collagen fibrils of the stroma in the cornea.{{cite journal| pmc=4655862 | pmid=26145225 | doi=10.1016/j.preteyeres.2015.07.001 | volume=49 | title=Corneal structure and transparency | year=2015 | journal=Prog Retin Eye Res | pages=1–16 | last1 = Meek | first1 = KM | last2 = Knupp | first2 = C}}

Besides ordering of atoms, short-range ordering of vacancies are also possible. Example of systems with short-range ordering of oxygen-vacancies include oxygen-deficient stoichiometries of the superconductors {{chem2|YBa2Cu2O_{7−δ} }}, {{chem2|Nd_{2−x}Ce_{x}CuO_{4−y} }}; as well as perovskites and novel bismuth sillenites.Becerro, Ana I., et al. "The transition from short-range to long-range ordering of oxygen vacancies in CaFe_x Ti_1-x O 3− x/2 perovskites." Physical Chemistry Chemical Physics 2.17 (2000): 3933-3941.C. McCammon, A. Becerro, F. Langenhorst, R. Angel, S. Marion, and F. Seifert, Journal of Physics: Condensed Matter

12, 2969 (2000).C. Hou, A. Manthiram, L. Rabenberg, and J. Goodenough, Journal of Materials Research 5, 9 (1990).D. Werder, C. Chen, R. Cava, and B. Batlogg, Physical Review B 37, 2317 (1988) | https://doi.org/10.1103/PhysRevB.37.2317.Scurti, Craig A., et al. "Electron diffraction study of the sillenites Bi₁₂SiO₂₀, Bi₂₅FeO₃₉ and Bi₂₅InO₃₉: Evidence of short-range ordering of oxygen-vacancies in the trivalent sillenites." AIP Advances 4.8 (2014): 087125. | https://doi.org/10.1063/1.4893341