35Cl Nuclear Quadrupole Resonance in Some Solid-Mixtures of p-Dichlorobenzene

Abstract

The impurity effects on 35Cl NQR frequency in various binary systems of p-dichlorobenzene as solvent and napthalene derivatives as solute have been studied in the range of solute concentration from 0-50% at room temperature. It is found that there is a critical range of solute concentration where both β and α-phase of p-dichlorobenzene coexist. Below the lower limit of critical concentration the NQR frequency corresponds to β-phase of p-dichlorobenzene. An increase in the solute concentration is found to induce a phase transition and the solid mixture at higher concentration consists of micro crystals belonging to both β and α-phase of p-dichlorobenzene upto the upper limit of critical concentration beyond which only α-phase is found to be present. The phase diagrams indicate that the solubility of the two components in each other is limited. The effect caused by the formation of eutectic mixture hardly disturbs the electric field gradient.