Editing Mesomeric effect (section)

== Mesomeric effect vs. inductive effect ==
The net electron flow from or to the substituent is determined also by the [[inductive effect]].<ref name=":2" /> The mesomeric effect as a result of ''p''-[[Atomic orbital|orbital]] overlap (resonance) has absolutely no effect on this inductive effect, as the inductive effect has purely to do with the [[electronegativity]] of the atoms and their topology in the molecule (which atoms are connected to which). Specifically the inductive effect is the tendency for the substituents to repel or attract electrons purely based on electronegativity and not dealing with restructuring. The mesomeric effect however, deals with restructuring and occurs when the electron pair of the substituents shift around. The inductive effect only acts on alpha carbons, while the mesomeric utilizes pi bonds between atoms.<ref>{{Cite journal |last1=Clark |first1=D. T. |last2=Murrell |first2=J. N. |last3=Tedder |first3=J. M. |date=1963 |title=234. The magnitudes and signs of the inductive and mesomeric effects of the halogens |url=http://xlink.rsc.org/?DOI=jr9630001250 |journal=Journal of the Chemical Society (Resumed) |language=en |pages=1250–1253 |doi=10.1039/jr9630001250 |issn=0368-1769}}</ref> While these two paths often lead to the similar molecules and resonance structures, the mechanism is different. As such, the mesomeric effect is stronger than the inductive effect.<ref name=":3">{{Cite journal |last1=Streets |first1=D.G. |last2=Ceasar |first2=Gerald P. |date=October 1973 |title=Inductive and mesomeric effects on the π orbitals of halobenzenes |url=http://www.tandfonline.com/doi/abs/10.1080/00268977300102271 |journal=Molecular Physics |language=en |volume=26 |issue=4 |pages=1037–1052 |doi=10.1080/00268977300102271 |bibcode=1973MolPh..26.1037S |issn=0026-8976}}</ref>

The concepts of mesomeric effect, '''mesomerism''' and '''mesomer''' were introduced by [[Christopher Kelk Ingold|Ingold]] in 1938 as an alternative to [[Linus Pauling|Pauling's]] synonymous concept of resonance.<ref>{{cite journal|title=If It's Resonance, What Is Resonating? |last=Kerber |first=Robert C. |journal=[[J. Chem. Educ.]] |date=2006-02-01 |volume=83 |number=2 |page=223 |url=http://www.jce.divched.org/Journal/Issues/2006/Feb/abs223.html |doi=10.1021/ed083p223 |url-status=dead |archive-url=https://web.archive.org/web/20061004085840/http://www.jce.divched.org/Journal/Issues/2006/Feb/abs223.html |archive-date=2006-10-04 |bibcode=2006JChEd..83..223K }}</ref> "Mesomerism" in this context is often encountered in German and French literature, but in English literature the term "resonance" dominates.