Mesoscopic clustering in butanol isomers

The paper presents the results of studies on a mesoscopic self-assembling occurring in liquid state of hydrogen-bonded n-, sec-, and tert- butanols. In the first part of the paper it was revealed (basing on the literature data) that an unexpectedly high melting point of tert-butanol does not result from some extraordinary way of intermolecular clustering in that alcohol, but from an exceptional packing of its globular-like molecules. The conclusion arises from a similar behavior of neopentane - the non-polar analogue of tert-butanol. Our results of the static dielectric studies on butanol isomers, in particular the Kirkwood correlation factor and the orientation entropy increment show that the spatial arrangement of the hydrocarbon moiety surrounding -OH group, essentially determines the structure of emerging molecular dusters. The form of clusters are evolving from a chain-like in n-butanol to a great variety of branched entities (induding the cyclic ones) in tert-butanol. (C) 2020 Elsevier B.V. All rights reserved.