Zero‐field splitting and g‐Values of d⁸ ions in a trigonal crystal field

Abstract

On the basis of the crystal-field theory the zero-field splitting and g-values of the ,A, ground state for d* impurity ions in a trigonally distorted octahedral field are calculated. Using perturbation theory the analytical expressions connecting the spin-Hamiltonian parameters with the crystalfield parameters are obtained. It is shown that experimental data for Cu3+ in A1,0, and Ni2+ in Also,, a-LiIO,, LiNbO, can be explained taking into account the influence of all the excited levels on the ground state. Ha OCHOBe TeOpHH KpLICTaJIJIHYeCKOrO IlOJIR IIpOBeneH paCq&T PaCIUeIIJIeHHH B HyJIeBOM nOJIe COCTORHHII ,A, HJIR IIpHMeCHbIX ds HOHOB B OKTa3ZPH-IIeCKOM IlOJIe C TpHrOHaJlLHbIM HCKalfCeHHeM. MeTonoM TeOpHM BO3M~~eHH~ IIOJIyZIeHbI aHaJILITHYeCKHe BbIPaHEeHHR, CBII3bIBaIoIUHe IlapaMeTpbI CllHH-TaMHJIbTOHHaHa C IIapa-MeTpaMH IEPHCTaJIIJILIYeCKOTO IIOJIR. nOKa3aH0, ZIT0 3KCIIepEiMeHTaJIbHble AaHHbIe nJIFJ 6Y%J&HHbIX ypOBHefii, B3aHMOAe%CTBYIoIUHX C OCHOBHbIM COCTORHHeM. g-@aKTOPOB OCHOBHOFO cu3+ B A1,0, H Ni2+ B A]@,, a-LiIo, H LiNbO, MoHHO 06'6RcHk1~L npn yYeTe BceX B03-

Explanation of the Optical Spectra and Spin-Hamiltonian Parameters for Nickel(II) in Cadmium Bromide Crystal

“…According to the approximate relation D = − ζ d 4 (g −g ⊥ ) for 3d 8 electron configurations in trigonal symmetry [24], the ζ d > 0 and g-shift ∆g = g − g ⊥ > 0, thus, the negative sign of D can be regarded as reasonable.…”

Theoretical studies of the EPR parameters for Ni2+ and Co+ in MgO

“…When a 3d 8 ion locates on an octahedral (O h ) site, the free-ion configuration 3 F would be separated into two orbital doublets 3 T 1g and 3 T 2g and one singlet 3 A 2g , with the latter lying lowest corresponding to the isotropic g and A signals [16]. As for the g factor of a 3d 8 ion in octahedra, the perturbation formula was established using the conventional crystal-field model [17,18], by including only the contributions from the central ion orbital and spin-orbit coupling interactions. In order to study the EPR spectra of the 3d 8 centers more exactly, the ligand orbital and spin-orbit contributions may be taken into account.…”

“…κ is the core polarization constant. The energy denominators E i (i = 1 ∼ 3) denote the energy separations between the excited 3 T 2 , 1 T 2a and 1 T 2b and the ground 3 A 2 states [17][18][19]. They can be described in terms of the cubic field parameter Dq and the Racah parameters B and C for the 3d 8 ion in crystals: E 1 ≈ 10 Dq, E 2 ≈ 10 Dq + 12 B and E 3 ≈ 8 B + 2C + 10Dq [17][18][19].…”

Spin-Spin and Spin-Other-Orbit Interactions of Spin-Hamiltonian Parameters for 3d2(8)Ions in Al2O3Crystals

“…When transition metal (TM) ions are doped into Al 2 O 3 crystal for replacing Al 3+ ions, impurity defect centers are created. The spin-Hamiltonian (SH) parameters, including the zero field splitting (ZFS) parameter D and g factors (g , g ⊥ ), have been determined for V 3+ and Cr 4+ (3d 2 ) ions in Al 2 O 3 crystals in [8,14,15], whereas for Ni 2+ and Cu 3+ (3d 8 ) ions in [3,17]. The SH parameters of Ni 2+ and Cu 3+ ions in Al 2 O 3 crystals were explained theoretically based on the spin-orbit (SO) mechanism in [1,2].…”