Magnetic Properties of Novel Layered Disulfides CuCr0.99Ln0.01S2 (Ln = La…Lu)

Abstract

The comprehensive study of the lanthanide-doped solid solutions CuCr0.99Ln0.01S2 (Ln = La…Lu) magnetic properties was carried out using static magnetochemistry and differential scanning calorimetry techniques. It was shown that magnetic properties of CuCr0.99Ln0.01S2 are significantly affected by the magnetic properties of the lanthanide ion. The magnetic susceptibility and the effective magnetic moment were found to deviate from the Curie-Weiss law in the temperature 90 K below and 50 K above the order-disorder transition at 695 K. The observed behavior of the temperature dependence of the effective magnetic moment in the order-disorder transition temperature region was described as a result of copper atoms redistribution over different types of the crystallographic sites.

Charge Distribution in Layered Lanthanide-Doped CuCr0.99Ln0.01S2 (Ln = Pr–Tb) Thermoelectric Materials

“…Taking into account the obtained data on the charge distribution on the metal and sulfur atoms in CuCr 0.99 Ln 0.01 S 2 , one can conclude that cationic substitution occurs via the isovalent mechanism Cr 3+ →Ln 3+ , which is in good agreement with previously reported studies of CuCr 0.99 Ln 0.01 S 2 magnetic properties [19,42]. For instance, the experimental value of the effective magnetic moment for CuCr 0.99 Ln 0.01 S 2 correlated with the theoretical values that consider Cr 3+ →Ln 3+ isovalent substitution [42]. It should be noted that magnetic susceptibility is a macroscopic property of chemical compounds, whereas XPS spectroscopy allows one to analyze the oxidation state of elements directly [32,39,41].…”

“…Thus, the data analyzed allowed one to conclude that the oxidat of lanthanide atoms in CuCr0.99Ln0.01S2 is Ln 3+ . The absence of significant chemic (≥0.2 eV, taking into account recoil effects and the crystal lattice vibrations) of th ured copper, chromium and sulfur XPS lines indicated electron density preservat ing both the cationic substitution process and variation of the lanthanide elemen Taking into account the obtained data on the charge distribution on the m sulfur atoms in CuCr0.99Ln0.01S2, one can conclude that cationic substitution occur isovalent mechanism Cr 3+ →Ln 3+ , which is in good agreement with previously r studies of CuCr0.99Ln0.01S2 magnetic properties [19,42]. For instance, the experimen magnetic moment value, the most significant increase in Seebeck coefficient valu served for the samarium-doped solid solution (S = 148 µ V/K).…”

“…The XES data indicated the absence of Cu 2+ states in the bulk for CuCrS2-based solid solutions. This fact was additionally approved by magnetic susceptibility measurements [19,41,42]. Thus, one can conclude that the oxidation state of copper atoms in the composition of CuCr0.99Ln0.01S2 (Ln = Pr-Tb) solid solutions is Cu + .…”

One-Pot Synthesis and Characterization of CuCrS2/ZnS Core/Shell Quantum Dots as New Blue-Emitting Sources

“…In addition, to analyze the crystal structure of the CCS QDs, we employed thin film and powder XRD techniques ( Figure 2 d). The XRD pattern of CuCrS 2 core showed weak and broad peaks at 33.13°, 36.17°, 49.46°, and 51.89° indicating the (102), (104), (108), and (110) phases of hexagonal CuCrS 2 , respectively [ 19 ]. The absence of a (101) phase at around 30° was probably attributed to the partial release of Cu atoms at the washing step for XRD analysis.…”

The Charge Distribution, Seebeck Coefficient, and Carrier Concentration of CuCr0.99Ln0.01S2 (Ln = Dy–Lu)

“…The XRD patterns after the final sulfidation stage are plotted in Figure 1 a. The synthesized samples were composed of a single phase corresponding to the rhombohedral R3m space group [ 32 ]. The diffraction peak positions were in good agreement with the XRD data of the Inorganic Crystal Structure Database (ICSD) for the initial CuCrS 2 -matrix (ICSD ID 100594).…”