Editing Strontium chloride (section)

==Structure==
In the solid state, SrCl<sub>2</sub> adopts a [[Fluorite structure|fluorite]] structure.<ref>{{Cite book|last=West, Anthony R.|url=https://www.worldcat.org/oclc/854761803|title=Solid state chemistry and its applications|date=8 January 2014|isbn=978-1-118-67625-7|edition=Second edition, student|location=Chichester, West Sussex, UK|oclc=854761803}}</ref><ref>{{Citation|last=Persson|first=Kristin|title=Materials Data on SrCl<sub>2</sub> by Materials Project|date=2020|url=https://www.osti.gov/servlets/purl/1199327/|others=Materials Project|publisher=LBNL Materials Project; Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)|language=en|doi=10.17188/1199327|access-date=2020-10-10}}</ref><ref>{{Cite web|last1=Mark|first1=H.|last2=Tolksdorf|first2=S.|date=1925|title=Ueber das Beugungsvermoegen der Atome fuer Roentgenstrahlen.|url=http://www.crystallography.net/cod/1010899.html|access-date=2020-10-10|website=www.crystallography.net|language=en}}</ref> In the vapour phase the SrCl<sub>2</sub> molecule is non-linear with a Cl-Sr-Cl angle of approximately 130°.<ref name="Greenwood">{{Greenwood&Earnshaw}}</ref> This is an exception to VSEPR theory which would predict a linear structure. [[Ab initio]] calculations have been cited to propose that contributions from d orbitals in the shell below the valence shell are responsible.<ref>[[Ab initio]] model potential study of the equilibrium geometry of alkaline earth dihalides: MX<sub>2</sub> (M=Mg, Ca Sr, Ba; X=F, Cl, Br, I) Seijo L., Barandiarán Z ''J. Chem. Phys.'' 94, 3762 (1991) {{doi|10.1063/1.459748 }}</ref> Another proposal is that polarisation of the electron core of the strontium atom causes a distortion of the core electron density that interacts with the Sr-Cl bonds.<ref>"Ion model and equilibrium configuration of the gaseous alkaline-earth dihalides" Guido M. and Gigli G. ''J. Chem. Phys.'' 65, 1397 (1976); {{doi|10.1063/1.433247}}</ref>