Formulation of interaction potential using ultrasonic wave propagation in organic liquids

An expression for the interaction potential is formulated and it is applied to compute the exponent of repulsive forces of 45 normal and associated organic liquids. The measured values of ultrasonic velocity and density were used at room temperature (293 K) for most of the organic liquids; however, in other cases values at different temperatures were determined. The large departures in the value of the exponent are partly attributed to intermolecular hydrogen bonding wherever it is effective and also to chemical covalent bonding. The intermolecular hydrogen bonding increases the melting and boiling points as the molecular weight increases and it causes an increased value of association. The exponent of repulsive force is also found to be increased. The anisotropy of the potential arises as a result of associative behaviour of the molecules