Spin-Hamiltonian parameters of Yb³⁺ ions in trigonally-distorted octahedral sites of Na₃Sc₂V₃O₁₂ garnet

Abstract

The spin-Hamiltonian (SH) parameters (g factors, g _¶ and g _⊥, and hyperfine structure constants, ¹⁷¹ A _¶, ¹⁷¹ A _⊥, ¹⁷³ A _¶ and ¹⁷³ A _⊥) for Yb³⁺ ions in trigonally-distorted octahedral sites of Na₃Sc₂V₃O₁₂ garnet were calculated from a complete diagonalization (of energy matrix) method (CDM) concerning 4f¹³ ions in trigonal symmetry. In the method, the Zeeman and hyperfine interaction terms are added to the Hamiltonian in the conventional CDM and the crystal-field parameters are estimated from the empirical superposition model. From the calculations, these SH parameters are explained reasonably. The defect structure of Yb³⁺ impurity centres in Na₃Sc₂V₃O₁₂ garnet and the signs of ¹⁷¹ A_i (i = ¶ or ⊥) and ¹⁷³ A_i are also suggested. The intrinsic parameters in the superposition model obtained in the studied system show that > > . This point is consistent with the intrinsic parameters obtained for many rare earth ion systems and can be regarded as suitable.

Keywords:

• electron paramagnetic resonance
• spin-Hamiltonian parameters
• crystal and ligand field theory
• defect structure
• Yb³⁺
• Na₃Sc₂V₃O₁₂