Publication Type |
Journal Article |
Title |
Conformational analysis of branched alkanes using limiting partial molar volumes |
Authors |
Ester F. G. Barbosa Elsa V. Pereira A.F. Santos Isabel M. S. Lampreia |
Groups |
MTFT |
Journal |
JOURNAL OF CHEMICAL THERMODYNAMICS |
Year |
2017 |
Month |
December |
Volume |
115 |
Number |
|
Pages |
84-90 |
Abstract |
The solvent effect on the solute conformations of straight and branched-chain alkanes infinitely diluted in methanol and carbon tetrachloride is studied. An additive scheme is used that takes into account the strong relation between limiting partial molar volumes and the average numbers of gauche conformations adopted by the solute molecules in each solvent. These numbers were determined using the Pitzer s steric partition function with different values of anti -> gauche transition enthalpy variations, ranging from (+2931 to -1465) kJ.mol(-1). The partial molar volumes at infinite dilution for three mono branched-chain alkanes (2-methylpentane, 3-methylpentane and 2-methylheptane) were experimentally determined in methanol to complement other series consisting mainly of straight, bi and tri branched-chain alkanes obtained in previous works. The conformational analysis performed using statistical methods is quite convincing about the strong effect of the solvent on the solute conformation equilibrium. Conclusions about close-packing and structure effects related to anti-gauche transitions in these two solvents are also drawn. (C) 2017 Elsevier Ltd. |
DOI |
http://dx.doi.org/10.1016/j.jct.2017.07.026 |
ISBN |
|
Publisher |
|
Book Title |
|
ISSN |
0021-9614 |
EISSN |
1096-3626 |
Conference Name |
|
Bibtex ID |
ISI:000413418600011 |
Observations |
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