Structural and Magnetic Transformations from CuCl to Cu2Cl(OH)3 Induced by H2O and CuCl2

Abstract

This study explores the oxidation dynamics of “pure” CuCl during prolonged environmental exposure through X-ray diffraction and temperature-dependent magnetization assessments. While CuCl is traditionally considered diamagnetic, our investigation reveals the emergence of an antiferromagnetic transition at 4.7 K. This anomaly is potentially induced by the integration of water molecules into the CuCl matrix. The hydration process initiates a series of oxidation reactions, ultimately transmuting CuCl into Cu2Cl(OH)3. Over time, the distinctive diffraction pattern peaks corresponding to CuCl diminish, concurrently with the appearance and intensification of those ascribed to Cu2Cl(OH)3, culminating in a complete phase transition as confirmed by X-ray analysis. Correspondingly, magnetization measurements clearly discern magnetic transitions at 6.4 and 16 K, intensifying with the sample’s exposure duration. These findings illuminate the stark potential for probing the magnetic intricacies of Cu2Cl(OH)3, a subject that remains a compelling and unresolved intrigue within the field.