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Effective molarity

In chemistry, the effective molarity is defined as the ratio between the first-order rate constant of an intramolecular reaction and the second-order rate constant of the corresponding intermolecular reaction or the ratio between the equilibrium constant of an intramolecular reaction and the equilibrium constant of the corresponding intermolecular reaction.

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In chemistry, the effective molarity (denoted EM)1 is defined as the ratio between the first-order rate constant of an intramolecular reaction and the second-order rate constant of the corresponding intermolecular reaction (kinetic effective molarity)12 or the ratio between the equilibrium constant of an intramolecular reaction and the equilibrium constant of the corresponding intermolecular reaction (thermodynamic effective molarity).13

E M k i n e t i c = k i n t r a m o l e c u l a r k i n t e r m o l e c u l a r {\displaystyle EM_{kinetic}={k_{intramolecular} \over k_{intermolecular}}}
E M t h e r m o = K i n t r a m o l e c u l a r K i n t e r m o l e c u l a r {\displaystyle EM_{thermo}={K_{intramolecular} \over K_{intermolecular}}}

EM has the dimension of concentration. High EM values always indicate greater ease of intramolecular processes over the corresponding intermolecular ones. Effective molarities can be used to get a deeper understanding of the effects of intramolecularity on reaction courses.4

See also

See also

References

References

  1. Kirby, AJ in (1980). Advances in Physical Organic Chemistry. London: Academic Press. pp. 183–278. ISBN 9780120335176.
  2. Dougherty, Eric V. Anslyn ; Dennis A. (2006). Modern physical organic chemistry (Dodr. ed.). Sausalito, Calif.: University Science Books. p. 496. ISBN 9781891389313.{{cite book}}: CS1 maint: multiple names: authors list (link)
  3. Hunter, Christopher A.; Anderson, Harry L. (28 September 2009). "What is Cooperativity?". Angewandte Chemie International Edition. 48 (41): 7488–7499. doi:10.1002/anie.200902490.
  4. Krishnamurthy, Vijay M.; Semetey, Vincent; Bracher, Paul J.; Shen, Nan; Whitesides, George M. (1 February 2007). "Dependence of Effective Molarity on Linker Length for an Intramolecular Protein−Ligand System". Journal of the American Chemical Society. 129 (5): 1312–1320. doi:10.1021/ja066780e. PMC 2535942. PMID 17263415.