Editing Computational chemistry (section)

{{Short description|Branch of chemistry}}
{{this|simulation of chemicals|other uses of computers in chemistry|Category:Chemistry software}}
[[File:C60_isosurface.png|thumb|[[Fullerene|C<sub>60</sub> molecule]] with [[isosurface]] of ground-state electron density as calculated with [[density functional theory]]]]{{good article}}
'''Computational chemistry''' is a branch of [[chemistry]] that uses [[computer simulation]]s to assist in solving chemical problems.<ref>{{Cite book |url=https://onlinelibrary.wiley.com/doi/book/10.1002/9781119518068 |title=Reviews in Computational Chemistry, Volume 31 |date=2018-10-19 |volume=4 |publisher=Wiley |isbn=978-1-119-51802-0 |editor-last=Parrill |editor-first=Abby L. |edition=1 |language=en |doi=10.1002/series6143 |editor-last2=Lipkowitz |editor-first2=Kenny B.}}</ref> It uses methods of [[theoretical chemistry]] incorporated into [[computer program]]s to calculate the structures and properties of [[molecule]]s, groups of molecules, and solids.<ref>{{Citation |author=((National Research Council (US) Committee on Challenges for the Chemical Sciences in the 21st Century))|title=Chemical Theory and Computer Modeling: From Computational Chemistry to Process Systems Engineering |date=2003 |url=https://www.ncbi.nlm.nih.gov/books/NBK207665/ |work=Beyond the Molecular Frontier: Challenges for Chemistry and Chemical Engineering |access-date=2023-12-05 |publisher=National Academies Press (US) |language=en}}</ref>  The importance of this subject stems from the fact that, with the exception of some relatively recent findings related to the hydrogen molecular ion ([[dihydrogen cation]]), achieving an accurate quantum mechanical depiction of chemical systems analytically, or in a closed form, is not feasible.<ref>{{Cite journal |last1=Korobov |first1=Vladimir I. |last2=Karr |first2=J.-Ph. |date=2021-09-07 |title=Rovibrational spin-averaged transitions in the hydrogen molecular ions |url=https://link.aps.org/doi/10.1103/PhysRevA.104.032806 |journal=Physical Review A |volume=104 |issue=3 |pages=032806 |doi=10.1103/PhysRevA.104.032806|arxiv=2107.14497 |bibcode=2021PhRvA.104c2806K |s2cid=236635049 }}</ref> The complexity inherent in the [[many-body problem]] exacerbates the challenge of providing detailed descriptions of quantum mechanical systems.<ref>{{Cite book |last=Nozières |first=Philippe |title=Theory of interacting Fermi systems |date=1997 |publisher=Perseus Publishing |isbn=978-0-201-32824-0 |series=Advanced book classics |location=Cambridge, Mass}}</ref> While computational results normally complement information obtained by chemical [[experiment]]s, it can occasionally predict unobserved chemical [[phenomena]].<ref>{{Cite journal |last1=Willems |first1=Henriëtte |last2=De Cesco |first2=Stephane |last3=Svensson |first3=Fredrik |date=2020-09-24 |title=Computational Chemistry on a Budget: Supporting Drug Discovery with Limited Resources: Miniperspective |url=https://pubs.acs.org/doi/10.1021/acs.jmedchem.9b02126 |journal=Journal of Medicinal Chemistry |language=en |volume=63 |issue=18 |pages=10158–10169 |doi=10.1021/acs.jmedchem.9b02126 |pmid=32298123 |s2cid=215802432 |issn=0022-2623}}</ref>