Abstract
The intermolecular interaction of non-saturated (oleic acid) and saturated (stearic and myristic acids)
mono-carboxylic acids in a non-polar organic solvent (deuterated benzene) is derived from the concentration
dependence of the small-angle neutron scattering. The excluded volume repulsion dominates
over the attraction (supposed due to van derWaals forces) for oleic andmyristic acids. In turn, for stearic
acid the attractive component is higher than the repulsive one; this results in a shift of the transition into the liquid crystalline state (because of molecule anisotropy) towards smaller concentrations and could explain early data on worse stabilization properties of stearic acid in ferrofluids compared to oleic and
myristic acids.