| Autor: |
Emel'yanenko VN; Department of Physical Chemistry, University of Rostock, 18051 Rostock, Germany., Toktonov AV, Kozlova SA, Verevkin SP, Andrushko V, Andrushko N, Börner A |
| Jazyk: |
angličtina |
| Zdroj: |
The journal of physical chemistry. A [J Phys Chem A] 2008 May 01; Vol. 112 (17), pp. 4036-45. Date of Electronic Publication: 2008 Mar 25. |
| DOI: |
10.1021/jp7115033 |
| Abstrakt: |
Standard molar enthalpies of formation in the gaseous state of a series of alkyl 3-methylbut-2-enoates have been obtained from combustion calorimetry and results from the temperature dependence of the vapor pressure measured by the transpiration method. To verify the experimental data, we have performed ab initio calculations of all compounds. Enthalpies of formation derived from the G3MP2 method are in excellent agreement with the experimental results. Quantitative analysis of strain effects in alkyl 3-methylbut-2-enoates was discussed in terms of deviations of deltafH degrees m(g) from the group additivity rules. Energetics of the cis-trans isomerization of carboxylic acid derivatives was studied using G3MP2 and DFT methods. Values of strain and cis-trans corrections derived in this work provide further improvement on the group-contribution methodology for prediction of the thermodynamic properties of compounds relevant to biodiesel. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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