Editing Amorphous solid (section)

== Structure ==
[[File:Crystalline vs. Amorphous solid.png|thumb|Crystalline vs. amorphous solid]]
Amorphous materials have an internal structure of molecular-scale structural blocks that can be similar to the basic structural units in the crystalline phase of the same compound.<ref>{{cite journal | first1 = Juraj| last1 = Mavračić| first2 = Felix C.| last2 = Mocanu| first3 = Volker L.| last3 = Deringer| first4 = Gábor| last4 = Csányi| first5 = Stephen R.| last5 = Elliott| title = Similarity Between Amorphous and Crystalline Phases: The Case of TiO<sub>2</sub>|journal = [[J. Phys. Chem. Lett.]]| volume = 9| issue = 11| pages = 2985–2990| year = 2018| doi = 10.1021/acs.jpclett.8b01067| pmid = 29763315| url = https://www.repository.cam.ac.uk/handle/1810/283145| doi-access = free}}</ref> Unlike in crystalline materials, however, no long-range regularity exists: amorphous materials cannot be described by the repetition of a finite unit cell. Statistical measures, such as the atomic density function and [[radial distribution function]], are more useful in describing the structure of amorphous solids.<ref name=":6" /><ref name=":Z" />
[[File:Lake Mjøsa sunrise reflected in window 01.jpg|thumb|upright|[[Glass]] is a commonly encountered example of amorphous solids.]]
Although amorphous materials lack long range order, they exhibit localized order on small length scales.<ref name=":6" /> By convention, ''short range order'' extends only to the nearest neighbor shell, typically only 1-2 atomic spacings.<ref name=":0">{{Cite journal |last1=Cheng |first1=Y. Q. |last2=Ma |first2=E. |date=2011-05-01 |title=Atomic-level structure and structure–property relationship in metallic glasses |url=https://www.sciencedirect.com/science/article/pii/S0079642510000691 |journal=Progress in Materials Science |language=en |volume=56 |issue=4 |pages=379–473 |doi=10.1016/j.pmatsci.2010.12.002 |issn=0079-6425|url-access=subscription }}</ref> ''Medium range order'' may extend beyond the short range order by 1-2&nbsp;nm.<ref name=":0" />