Theoretical studies of the optical and EPR spectra for VO2+ in MgKPO4·6H2O single crystal

Theoretical studies of the optical and EPR spectra for VO^{2+} in Na_{3}C_{6}H_{5}O_{7}·2H_{2}O single crystal

“…this is consistent with a number of theoretical investigations [4,9,[19][20][21][22] and the previous calculation [11]. Therefore, the above calculated A and A ⊥ of the hyperfine structure constants for TSCD:VO 2+ are reasonable in signs and in magnitude.…”

“…VO 2+ in various crystal [4,10,[19][20][21][22], here, we take κ ≈ 0.80, which is comparable with that κ (≈ 0.72) obtained by the previous work and can be regarded as reasonable. Thus, the g factors, especially the anisotropy ∆g (= g ∥ − g ⊥ ) is connected with the tetragonal field parameters and hence with the local structure (i.e., the relative tetragonal elongation R ∥ − R ⊥ ) of the studied systems.…”

“…Thus, the g factors, especially the anisotropy ∆g (= g ∥ − g ⊥ ) is connected with the tetragonal field parameters and hence with the local structure (i.e., the relative tetragonal elongation R ∥ − R ⊥ ) of the studied systems. Due to the covalence reduction effect for 3d n ions in crystals, we have [19][20][21][22] ζ = N 2 ζ 0 and P = N 2 P 0 .…”

“…A 2 (R) and A 4 (R) are the intrinsic parameters with the reference distance R, where R (≈ R ⊥ ≈ 1.985 Å [17]) is taken for the VO 2+ in cubic field. For 3d n ions in octahedra, the ratio A 2 (R)/A 4 (R) is in the range of 9-12 in many crystals [4,12,13,[18][19][20]. Here, we take the mean value, i.e.…”

A comparable study of the optical spectra and EPR parameters for 3d1‐ and 3d9‐doped MgNH4PO4·6H2O

“…[14,15] 2.1 | LS and d-d transition bands for VO 2+ and Cu 2+ centers in MPPH Based on the anisotropy of the experimental g factors (Δg < 0 [14] ) and optical absorption bands for the studied VO 2+ center in MPPH, the [VO(H 2 O) 5 ] 2+ cluster can be reasonably ascribed to the tetragonally compressed octahedron. [18,19] The low symmetrical distortion is attributed to the JT effect via the vibrational interaction of the [VO (H 2 O) 5 ] 2+ cluster. Conveniently, for the studied tetragonally compressed [VO(H 2 O) 5 ] 2+ cluster, the two parallel (a short axial bond length R jj and an elongated axial bond length R jj 0 ) and the four elongated perpendicular bond lengths R ⊥ due to the significant compression distortion (i.e., positive compression ratio τ V ), the above local bond lengths can be expressed in terms of the reference (or average) metal-ligand distance R and the relative compression ratio τ V along C 4 -axial as (see Figure 1)…”