Editing VSEPR theory (section)

==History==
The idea of a correlation between molecular geometry and number of valence electron pairs (both shared and unshared pairs) was originally proposed in 1939 by [[Ryutaro Tsuchida]] in Japan,<ref>{{cite journal|journal= Nippon Kagaku Kaishi|volume=60 |year=1939|issue=3|pages= 245–256|doi=10.1246/nikkashi1921.60.245|script-title=ja:新簡易原子價論 |trans-title=New simple valency theory|first=Ryutarō |last=Tsuchida|language=ja|title=A New Simple Theory of Valency |doi-access=free}}</ref> and was independently presented in a [[Bakerian Lecture]] in 1940 by [[Nevil Sidgwick]] and [[Herbert Marcus Powell|Herbert Powell]] of the [[University of Oxford]].<ref>{{cite journal | last1 = Sidgwick | first1 = N. V. | last2 = Powell | first2 = H. M. | year = 1940 | title = Bakerian Lecture. Stereochemical Types and Valency Groups | journal = Proc. R. Soc. A | volume = 176 | issue = 965| pages = 153–180 | doi=10.1098/rspa.1940.0084| bibcode = 1940RSPSA.176..153S | doi-access = free }}</ref> In 1957, [[Ronald Gillespie]] and [[Ronald Sydney Nyholm]] of [[University College London]] refined this concept into a more detailed theory, capable of choosing between various alternative geometries.<ref name="Gill1957">{{cite journal | last1=Gillespie|first1=R. J.|author1-link=Ronald Gillespie|last2=Nyholm|first2=R. S.|author2-link=Ronald Sydney Nyholm| year = 1957 | title = Inorganic stereochemistry | journal = Q. Rev. Chem. Soc. | volume = 11 |issue=4| page = 339|doi=10.1039/QR9571100339 }}</ref><ref>{{cite journal | year = 1970 | last1=Gillespie|first1=R. J.|author1-link=Ronald Gillespie|title = The electron-pair repulsion model for molecular geometry | journal = J. Chem. Educ. | volume = 47 | issue = 1 | page = 18 |doi=10.1021/ed047p18|bibcode=1970JChEd..47...18G}}</ref>