6533b85dfe1ef96bd12be717

RESEARCH PRODUCT

Molecular association and dynamics in n-pentanol and 2-methyl-2-butanol

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description

Static dielectric constant, viscosity, density, ultrasonic and dielectric relaxation measurements are reported for two pentanol isomers (n-pentanol and 2-methyl-2-butanol) in a wide range of temperatures. The results show a different extent of H-bonds self-association in relation to the molecular geometry of the alcohol. The activation energies obtained from dielectric and ultrasonic studies are compared with those obtained from viscous flow. Such a comparison, together with the analysis of all the dielectric and ultrasonic relaxation data, show that in n-pentanol a correlation between viscosity and ultrasonic relaxation exists, while dielectric relaxation is not correlated with the other two processes. This finding has been rationalized in terms of different mechanisms. In 2-methyl-2-butanol a correlation between ultrasonic and dielectric relaxation processes has been observed. Additional contribution of ultrasonic absorption associated with isomeric internal rotational of the molecules has been assumed ...