Densities, Speeds of Sound and Heat Capacities of Binary and Ternary Mixtures Containing Cyclic Amines, Lactam and Pyridine

The densities, rho, speeds of sound, u, of binary piperidine or 1-methylpiperidine (1) + 2-pyrrolidinone or pyridine (2), and densities, rho(123), speeds of sound, u(123), of ternary piperidine or 1-methylpiperidine (1) + 2-pyrrolidinone (2) + pyridine (3) mixtures and molar heat capacities, C-P, for the aforesaid binary mixtures have been measured over the entire composition range at temperatures ranging from (293.15-308.15) K with an increment of 5 K. The excess molar volumes V-E, V-123(E), excess isentropic compressibilities, kappa(E)(S), (kappa(E)(S))(123) for the binary and ternary mixtures and excess heat capacities, C-P(E), for investigated binary mixtures (determined by using experimental data) were fitted with the Redlich-Kister equations, and adjustable binary as well as ternary parameters along with the standard deviations have been estimated. The analyses of V-E, kappa(E)(S), C-P(E) data, quantum mechanical calculations and IR spectra of binary mixtures have revealed that piperidine (1) + 2-pyrrolidinone (2) mixtures are characterized by interactions between nitrogen and hydrogen atoms of piperidine with the hydrogen and oxygen atoms of 2-pyrrolidinone; 1-methylpiperidine (1) + 2-pyrrolidinone (2) mixtures are characterized by interactions between nitrogen and electron deficient carbon atom of 1-methylpiperidine with hydrogen and oxygen atoms of 2-pyrrolidinone; piperidine (1) + pyridine (2) mixtures are characterized by interactions between the hydrogen atom of piperidine with the nitrogen atom of pyridine; 1-methylpiperdine (1) + pyridine (2) mixtures are characterized by the interaction of the nitrogen atom of 1-methylpiperidine with the pi-electron cloud of pyridine's aromatic ring.

Automated summary

The properties of binary and ternary mixtures of piperidine, 1-methylpiperidine, 2-pyrrolidinone, and pyridine have been studied at different temperatures, with parameters fitted using experimental data. The results indicate that the properties of the mixtures are influenced by intermolecular interactions.