Conformational kinetics of methyl nitrite. II. Phase dependence of kinetic parameters
- 15 April 1984
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 80 (8) , 3561-3568
- https://doi.org/10.1063/1.447148
Abstract
Temperature and pressure dependent exchange broadened NMR spectra of gaseous methyl nitrite are consistent with the following kinetic parameters for the syn–anti conformational interconversion: Eact (∞), 12.2(4) kcal/mol; Eact (bimolecular), 9.6(2) kcal/mol; ΔH‡, 11.7(4) kcal/mol; ΔG‡298 11.97(7) kcal/mol; and ΔS‡298 , −0.9(4) cal/mol K. Kinetic parameters for interconversion in the neat liquid and in a 1% solution in CS2 are slightly higher: Eact; 12.9(2); ΔH‡, 12.4(2) kcal/mol; ΔG‡, 11.81(8) kcal/mol; and ΔS‡, 2.6(2) cal/mol K. These remarkably small solvent effects indicate that dielectric effects on conformational dynamics in this system are nearly equal in magnitude and opposite in direction to solvent internal pressure effects.Keywords
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