RT info:eu-repo/semantics/article
T1 Thermodynamics of mixtures with strongly negative deviations from Raoult's law. XV. Permittivities and refractive indices for 1-alkanol + n-hexylamine systems at (293.15–303.15) K. Application of the Kirkwood-Fröhlich model
A1 Hevia, Fernando
A1 González, Juan Antonio
A1 Cobos, Ana .
A1 García de la Fuente, Isaías
A1 Alonso Tristán, Cristina
K1 1-alkanol
K1 n-hexylamine
K1 Permittivity
K1 Refractive index
K1 Kirkwood correlation factor
K1 Electric engineering
K1 Ingeniería eléctrica
AB Relative permittivities at 1 MHz, , and refractive indices at the sodium D-line, , are reported at 0.1 MPa and at (293.15–303.15) K for the binary systems 1-alkanol + n-hexylamine (HxA). Also, their corresponding excess functions are calculated and correlated. Positive values of the excess permittivities, , are encountered for the methanol system, whereas the remaining mixtures show negative values. This reveals that interactions between unlike molecules contribute positively to . This contribution is dominant for the methanol mixture, while those arising from the breaking of interactions between like molecules are prevalent for the remaining mixtures. At  (volume fraction) = 0.5,  changes in the order: methanol > 1-propanol > 1-butanol > 1-pentanol < 1-heptanol. Similar variation with the chain length of the 1-alkanol is observed for mixtures such as 1-alkanol + heptane, or + cyclohexylamine, and can be explained in terms of the lower and weaker self-association of longer 1-alkanols. The effect of the replacement of HxA by cyclohexylamine, or by aniline, is also shown. Calculations on molar refractions indicate that dispersive interactions in the systems under study increase with the length of the 1-alkanol. The mixtures are studied by means of the application of the Kirkwood-Fröhlich model, and the Kirkwood correlation factors, including the corresponding excess values, are reported.
PB Elsevier
SN 0378-3812
YR 2018
FD 2018-07
LK http://hdl.handle.net/10259/4791
UL http://hdl.handle.net/10259/4791
LA eng
NO Ministerio de Educación, Cultura y Deporte for the grants FPU14/04104 and FPU15/05456 respectively. The authors gratefully acknowledge the financial support received from the Consejería de Educación y Cultura of Junta de Castilla y León, under Project BU034U16.
DS Repositorio Institucional de la Universidad de Burgos
RD 28-abr-2024