Theoretical studies of the local structures and EPR parameters for Cu\(^{2+}\) center in Cd\(_{2}\)(NH\(_{4}\))\(_{2}\)(SO\(_{4}\))\(_{3}\) single crystal

• Published in: arXiv.org 2015-12
• Main Authors: Ch -Y Li, L -B Chen, J -J Mao, X -M Zheng
• Format: Article
• Language: English
• Subjects: Admixtures; Crystals; Electron paramagnetic resonance; Hyperfine structure; Parameters; Perturbation methods; Single crystals; Superposition (mathematics)
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1512.07796

The electron paramagnetic resonance (EPR) parameters (\(g\) factors \(g_{i}\) and the hyperfine structure constants \({{A}}_{{i}}\), \({i} = {x}, {y}, {z}\)) are interpreted by using the perturbation formulae for a \(3{d}^{9}\) ion in rhombically ({D}\(_{2h}\)) elongated octahedra. In the calculated formulae, the crystal field parameters are set up from the superposition model, and the contribution to the EPR parameters from the admixture of \(d\)-orbitals in the ground state wave function of the Cu\(^{2+}\) ion was taken into account. Based on the calculation, local structural parameters of the impurity Cu\(^{2+}\) center in Cd\(_{2}\)(NH\(_{4}\))\(_{2}\)(SO\(_{4}\))\(_{3}\) (CAS) crystal were obtained (i.e., \({R}_{{x}}\approx 2.05\) Å, \({R}_{{y}} \approx 1.91\) Å, \({R}_{{z}} \approx 2.32\) Å). The theoretical EPR parameters based on the above Cu\(^{2+}\)-O\(^{2-}\) bond lengths in CAS crystal show a good agreement with the observed values. The results are discussed.