This paper reports the role of hydrogen bonding and other electrostatic interactions on the dielectric behaviour, excess parameters, and structure properties of the binary systems containing 1-pentanol isomers (H-bond donors) and dipolar aprotic liquids at T = 298.15 K. The dipolar aprotic liquids were four H-bond acceptor, i.e. dimethyl ketone (acetone), methyl ethyl ketone (2-butanone), methyl phenyl ketone (acetophenone), and dimethyl sulfoxide (DMSO). In order to make a coherent discussion, the dielectric data were analyzed with various approaches in terms of intermolecular interactions between like and unlike molecules. In order to obtain valuable information about hetero interaction and structure occurring in the studied systems, the effective and corrective Kirkwood correlation factors were calculated using Kumbharkhane et al. approach. The Winkelmann-Quitzsch theory was employed to obtain excess Helmholtz energies of dipole-dipole interactions. The Reis and Iglesias approach was applied to calculate excess Kirkwood correlation factors. (C) 2017 Elsevier Ltd.