Thermodynamic and topological investigations in binary mixtures containing nitrobenzene

Abstract

Molar excess volumes, <i>V</i>^E, and molar excess enthalpies, <i>H</i>^E, for various nitrobenzene (i) + aniline, + N-methylaniline and + N,N-dimethylaniline (j) mixtures have been measured as a function of composition at 308.15 K. The observed data have been analysed in terms of graph-theoretical approach and Sanchez and Lacombe's approach. The analysis of <i>V</i>^E data by graph-theoretical approach reveals that nitrobenzene, aniline, N-methyl aniline and N,N-dimethyl aniline exist as associated entities and these mixtures are characterised by the interactions between the delocalised <i>π</i>- electron cloud over nitrogen and oxygen atoms of the nitro group of nitrobenzene and hydrogen atoms of aniline and N-methyl aniline. The present (i+j) mixtures contain 1:1 molecular complex. The IR studies lend additional support to the nature and extent of interactions for proposed structures in the mixtures. The energetics of the mixtures have also been discussed.