相关论文: Crystal-field splitting for low symmetry systems i…
K$_2$YF$_5$ crystals doped with lanthanide ions have a variety of possible optical applications. Owing to the low symmetry of the system, the crystal structure cannot be unambiguously determined by x-ray diffraction. However,…
Using a recently developed method combining a nonspherical self-interaction corrected LDA+$U$ scheme and an on-site multi-body Hamiltonian [Phys.\ Rev.\ B 83, 085106 (2011)], we calculate the crystal field parameters and crystal field (CF)…
In solids, crystal field splitting refers to the lifting of atomic orbital degeneracy by the surrounding ions through the static electric field. Similarly, we show that the degenerated $d$ orbitals, which were derived in the harmonic…
We study the correlated quantum magnet, YbCl$_3$, with neutron scattering, magnetic susceptibility, and heat capacity measurements. The crystal field Hamiltonian is determined through simultaneous refinements of the inelastic neutron…
A simple method for constructing effective Hamiltonians for the 4fN and 4fN-15d energy levels of lanthanide ions in crystals from quantum-chemical calculations is presented. The method is demonstrated by deriving crystal-field and…
The electronic structure of the honeycomb lattice iridates Na2IrO3 and Li2IrO3 has been investigated using resonant inelastic x-ray scattering (RIXS). Crystal-field split d-d excitations are resolved in the high-resolution RIXS spectra. In…
It has been shown that to calculate the parameters of the electrostatic field of the ion crystal lattice it sufficient to take into account ions located at a distance of 1-2 lattice spacings. More distant ions make insignificant…
We present a systematic study of the crystal field interactions in the Li$R$F$_4$, $R$ = Gd, Ho, Er, Tm and Yb, family of rare-earth magnets. Using detailed inelastic neutron scattering measurements we have been able to quantify the…
The crystal field parameters of 13 trivalent lanthanide ions substituted for La in LaF$_3$ were calculated using the combination of the band structure and Wannier function calculations. Performing an atomic exact diagonalization with thus…
We present an effective ab initio method to calculate the crystal field coefficients of an erbium (Er3+) ion experiencing different local site symmetries in several wide-band-gap oxides, and then evaluate crystal field splittings of these…
We present a method of calculating crystal field coefficients of rare-earth/transition-metal (RE-TM) magnets within density-functional theory (DFT). The principal idea of the method is to calculate the crystal field potential of the yttrium…
Crystal-field excitations, for example in transition-metal oxides where a rare-earth element is used as a spacer between the transition-metal-oxide tetrahedra and octahedra, are assumed to be extremely robust with respect to external…
Crystal field level scheme of a uniaxial chiral helimagnet YbNi$_3$Al$_9$, exhibiting a chiral magnetic soliton lattice state by Cu substitution for Ni, has been determined by inelastic neutron scattering. The ground and the first excited…
We discuss the calculation of crystal field splittings using Wannier functions and show how the ligand field contributions can be separated from the bare Coulomb contribution to the crystal field by constructing sets of Wannier functions…
The effective crystal field Hamiltonian provides the key description of the electronic properties of single-ion magnets, but obtaining its parameters from ab initio computation is challenging. We introduce a simple approach to derive the…
The relationship between the energy total splitting $\Delta E$ of the free-ion electron states in the axial crystal-fields and the second moment of that splitting $\sigma^{2}$ is thoroughly investigated. The non-Kramers and Kramers states…
Parametrized crystal-field analyses are presented for both the six and seven fold coordinated, C$_{1}$ symmetry Sm$^{3+}$ centers in Y$_{2}$SiO$_{5}$, based on extensive spectroscopic data spanning the infrared to optical regions. Laser…
We use complementary optical spectroscopy methods to directly measure the lowest crystal-field energies of the rare-earth quantum magnet LiY$_{1-x}$Ho$_{x}$F$_{4}$, including their hyperfine splittings, with more than 10 times higher…
Thermal electronic excitations in metal crystals are calculated by starting with a reference structure for the nuclei: the crystal structure of the appropriate phase. Here we explain the corresponding theory for metal liquids, starting with…
We apply the first-principles density functional theory + dynamical mean field theory framework to evaluate the crystal field splitting on rare earth sites in hard magnetic intermetallics. An atomic (Hubbard-I) approximation is employed for…