Some Physicochemical and Thermal Studies on Organic Analog of a Nonmetal-Nonmetal Monotectic Alloy; 2-Cyanoacetamide–4-chloronitrobenzene System

Abstract

The phase equilibrium data on organic analog of the nonmetal-nonmetal system, involving 2-cyanoacetamide (CA)-4-chloronitrobenzene (CNB), show the formation of a monotectic (0.10 mole fraction of CNB) and a eutectic (0.98 mole fraction of CNB) with a large miscibility gap starting from 0.10 mole fraction of CNB of monotectic (M) and ending at 0.92 mole fraction of CNB of monotectic horizontal (M h ); the upper consolute temperature T c being 63˚C above the monotectic horizontal at 118˚C and eutectic temperature is at 85˚C. The values of enthalpy of fusion of the pure components, the eutectic and the monotectic were determined by the differential scanning calorimetry (Mettler DSC-4000 system). Using these data, the size of the critical radius, interfacial energy, excess thermodynamic functions, entropy of fusion, and enthalpy of mixing were calculated. The solid-liquid interfacial energy data confirm the applicability of the Cahn wetting condition. While growth data obey the Hillig-Turnbull equation, the microstructural investigations give typical characteristic features of the eutectic and the monotectic of the system.

Forecast of Phase Diagram for the Synthesis of a Complex for the Detection of Cr6+ Ions

“…Other thermodynamic information, such as the interfacial energy, the roughness parameter, and the grain boundary energy, which help in crystal growth and significantly influence the morphology of the crystal were also calculated using heat of fusion values. The interfacial energies were calculated by using the formula where N A is the Avogadro number, V M is the molar volume, and parameter C is a constant lying between 0.30 and 0.35. The value of C used for calculation was 0.35.…”

Solidification and thermodynamic parameters of binary faceted organic alloys: Picric acid–Resorcinol system

“…Organic crystals have been studied since past half century [1][2][3][4] as the model materials to test the validity of several diffusion model solidification theories for eutectics and dendrites. Due to low melting temperature and transparency, these systems have played very important roles in enhancing the faceted and nonfaceted materials.…”

Remarkable dielectric properties of 1 : 2 inter-molecular compound of 2-(4-(dimethylamino) benzylideneamino) benzoic acid and urea due to excited-state intramolecular proton transfer

“…The phase diagram of DMABAB and U was determined using the thaw-melt method 14 by taking mixtures of DMABAB and U in the entire compositional range and sealing them in test tubes to avoid the loss of molecules. They were then homogenized by melting followed by cooling in ice cold water 5 times.…”