Heat capacity anomalies of associated liquid-alkane mixtures near the liquid-liquid critical point

The isobaric heat capacity for a set of critical binary mixtures composed by an associated liquid and an alkane was measured near the liquid-liquid critical point. From a careful analysis of experimental data, nonuniversal quantities such as critical temperatures and critical amplitudes were obtained. To obtain microscopic parameters that may characterise the critical behaviour of the studied systems, the critical amplitude of the correlation length was determined via two-scale factor universality. Useful insights into the influence of the molecular structure of the alkanes as well as the self-associating capability of the polar liquid on the aforementioned nonuniversal quantities are obtained.