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We report our spectroscopic studies of the d 3Π state of ultra-cold 7Li85Rb using resonantly enhanced multi-photon ionization and depletion spectroscopy with bound-to-bound transitions originating from the metastable a ³Σ+ state. We evaluate the potential of this state for use as the intermediate state in a stimulated-Raman-adiabatic-passage transfer scheme from triplet Feshbach LiRb molecules to the X ¹&#931+ ground state and find that the lowest several vibrational levels possess the requisite overlap with initial and final states, as well as convenient energies. Using depletion measurements, we measured the well depth and spin-orbit splitting. We suggest possible pathways for short-range photoassociation using deeply bound vibrational levels of this electronic state. [ABSTRACT FROM AUTHOR]

The newly synthesized phosphorus‐ and arsenic‐containing analogues of the thio‐ and seleno‐cyanate anions, PCSe−, AsCS−, and AsCSe−, as well as the known ion NCSe− were investigated in the gas phase by negative‐ion photoelectron spectroscopy (NIPES), velocity‐map imaging (VMI) spectroscopy, and quantum‐chemical computations. The electron affinities (EA), spin–orbit (SO) splittings, and "symmetric"/"asymmetric" stretching frequencies of the neutral radicals ECX. (E=N, P, As; X=S, Se), generated by electron detachment from the corresponding anions, were obtained from the spectra. The calculated EAs, SO splittings, and vibrational frequencies are in excellent agreement with the experimental measurements. These newly obtained values, when combined with those previously determined for the lighter analogues, show interesting trends on descending the pnictogen and chalcogen series. These trends are rationalized based on electronegativity arguments, the electron distributions in the HOMOs, and NBO/NRT analyses. [ABSTRACT FROM AUTHOR]

The intrachain magnetic interaction and the electronic structure of Sr3NiIrO6 are investigated by performing the first-principles density functional calculations. The results show that the interaction between Ir and Ni is antiferromagnetic in each quasi-one-dimensional chain. More importantly, the GGA+U calculations hardly reproduce the insulating characteristics of Sr3NiIrO6 in the region of reasonable correlation parameter. Interestingly, the spin-orbit coupling (SOC) together with the electron-electron correlation (GGA+SOC+U) can lead to the insulating characteristics of Sr3NiIrO6. This provides apparent evidence that Sr3NiIrO6 belongs to a new category of insulator: SOC induced Mott insulator. [ABSTRACT FROM AUTHOR]

The intrachain magnetic interaction and the electronic structure of Sr3NiIrO6 are investigated by performing the first-principles density functional calculations. The results show that the interaction between Ir and Ni is antiferromagnetic in each quasi-one-dimensional chain. More importantly, the GGA+U calculations hardly reproduce the insulating characteristics of Sr3NiIrO6 in the region of reasonable correlation parameter. Interestingly, the spin-orbit coupling (SOC) together with the electron-electron correlation (GGA+SOC+U) can lead to the insulating characteristics of Sr3NiIrO6. This provides apparent evidence that Sr3NiIrO6 belongs to a new category of insulator: SOC induced Mott insulator. [ABSTRACT FROM AUTHOR]

We measured the photoelectron spectra of diatomic AuSi- and AuGe- and conducted calculations on the structures and electronic properties of AuSi-/0 and AuGe-/0. The calculations at the CASSCF/CASPT2 level confirmed that experimentally observed spectra features of AuSi- and AuGe- can be attributed to the transitions from the 3Σ- anionic ground state to the 2Π (2Π1/2 and 2Π3/2), 4Σ-, 32Σ+, and 42Σ+ electronic states of their neutral counterparts. The electron affinities (EAs) of AuSi and AuGe are determined by the experiments to be 1.54 ± 0.05 and 1.51 ± 0.05 eV, respectively. The spin-orbit splittings (2Π1/2-2Π3/2) of AuSi and AuGe measured in this work are in agreement with the literature values. The energy difference between the 4Σ- (A) and 2Π1/2 states of AuSi obtained in this work is in reasonable agreement with the literature value, while that of AuGe obtained in this work by anion photoelectron spectroscopy is slightly larger than the literature value by neutral emission spectroscopy. The term energies of the 32Σ+ (B) and 42Σ + (C) states of AuSi and AuGe were also determined based on the photoelectron spectra. Because of the different bond lengths between the anionic and neutral states, the electronic state terms energies of AuSi and AuGe estimated from the anion photoelectron spectra might be slightly different from those obtained from the neutral emission spectra. [ABSTRACT FROM AUTHOR]

The electronic structure of Fe adsorbed g-C 2 N with different layers is investigated by first-principles calculations. The Fe 1 and Fe 2 represent the Fe adsorptions at C C and C N rings, and Fe 11 and Fe 121 adsorption sites are also considered. The Fe 1 adsorbed g-C 2 N is metallic with layer from n  = 1 to 4, and the maximum spin splitting is 515, 428, 46 and 133 meV. The band gap of Fe 2 adsorbed g-C 2 N with different layers is 0, 0, 117 and 6 meV, and the maximum spin splitting is 565, 369, 195 and 146 meV, respectively. All of the Fe 11 adsorbed g-C 2 N are metallic with layer from n  = 1 to 4, and the maximum spin splitting is 199, 0, 83 and 203 meV. An indirect band gap of 215 meV appears in Fe 121 adsorbed g-C 2 N at layer n  = 3, and the maximum spin splitting is 283, 211, 304 and 153 meV, respectively. Our results show that the electronic structures of Fe adsorbed novel two-dimensional semiconductor g-C 2 N can be tuned by different layers. Moreover, the spin splitting of Fe 2 adsorbed g-C 2 N decreases monotonically as g-C 2 N layer increases from n  = 1 to 4, which will provide more potential applications in spintronic devices. [ABSTRACT FROM AUTHOR]

In this contribution, we describe fundamental electronic structures and spin–charge–orbital orderings of 5 d transition-metal compounds. By reviewing photoemission spectroscopy studies on CuIr 2 S 4 , IrTe 2 , Cs 2 Au 2 Br 6 , and AuTe 2 , we discuss the difference between the t 2 g and e g systems with respect to the spin–orbit splitting versus the Jahn–Teller splitting. In contrast to the Ir oxides with Mott-Hubbard character, the smallness of the charge-transfer energy plays essential roles in the exotic spin–charge–orbital orderings of the Ir and Au chalcogenides and halides. In particular, the Te 5 p hole provides an interesting interplay between the charge–orbital order and the spin–orbit interaction in IrTe 2 . [ABSTRACT FROM AUTHOR]

Here, we present a detailed study on the temperature and angular dependence of the Shubnikov–de Haas (SdH) effect in the semimetal WTe2. This compound was recently shown to display a very large nonsaturating magnetoresistance which was attributed to nearly perfectly compensated densities of electrons and holes. We observe four fundamental SdH frequencies and attribute them to spin-orbit split, electron-like, and hole-like Fermi-surface (FS) cross-sectional areas. Their angular dependence seems consistent with ellipsoidal FSs with volumes suggesting a modest excess in the density of electrons with respect to that of the holes. We show that density functional theory (DFT) calculations fail to correctly describe the FSs of WTe2. When their cross-sectional areas are adjusted to reflect the experimental data, the resulting volumes of the electron/hole FSs obtained from the DFT calculations would imply a pronounced imbalance between the densities of electrons and holes. We find evidence for field-dependent Fermi-surface cross-sectional areas by fitting the oscillatory component superimposed onto the magnetoresistivity signal to several Lifshitz-Kosevich components. We also observe a pronounced field-induced renormalization of the effective masses. Taken together, our observations suggest that the electronic structure of WTe2 evolves with the magnetic field due to the Zeeman splitting. This evolution is likely to contribute to its pronounced magnetoresistivity. [ABSTRACT FROM AUTHOR]

The diatomic ZrO- anion has been prepared by laser ablation and studied by photoelectron imaging spectroscopy combined with quantum chemistry calculations. The observed photoelectron spectra can be well assigned on the basis of reported optical spectroscopy and high-level ab initio calculations. The ground state of ZrO- is a 2Δ state with spin-orbit splitting of 578±12 cm-1. The electron affinity of ZrO is 1.249±0.005 eV. For the first time, the c3∑- state of ZrO has been experimentally observed at 13316±24 cm-1 with respect to the X1∑+ ground state. A comparison between ZrO and the isoelectronic molecule NbN has been made. [ABSTRACT FROM AUTHOR]

• The laser-induced fluorescence excitation spectra and single-vibronic-level emission spectra of the ruthenium monoxide (RuO) molecule are investigated using laser ablation of a ruthenium target and reaction with a free jet expansion of oxygen. • Sixteen excitation bands are experimentally observed and grouped into the transition systems from the ground X 5Δ 4 and X 5Δ 3 states to six excited electronic states. The spin-orbit splitting between the X 5Δ 4 and X 5Δ 3 states is determined to be 399.44(2) cm−1. • The electronic structure of RuO in the low-lying states is discussed based on high-level ab initio calculations. The laser-induced fluorescence excitation spectra and single-vibronic-level emission spectra of ruthenium monoxide (RuO) molecule have been investigated using laser ablation of a ruthenium target and reaction with a free jet expansion of oxygen. Sixteen excitation bands have been experimentally observed in the energy range of 13,800 – 19,250 cm–1 and grouped into transition systems from the ground X 5Δ 4 and X 5Δ 3 states to six excited electronic states. The molecular constants, including the spin-orbit splittings, the rotational constants and the vibrational frequencies, in the ground and excited electronic states were obtained through rotational analysis of the spectra. The electronic structure has been discussed based on high-level ab initio calculations. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) is applied to study the atomic, electronic, and spin structures of the Au monolayer at the Ge(111) surface. It is found that the theoretically determined most stable atomic geometry is described by the conjugated honeycomb-chained-trimer (CHCT) model, in a very good agreement with experimental data. The calculated electronic structure of the system, being in qualitatively good agreement with the photoemission measurements, shows fingerprints of the many-body effects (self-interaction corrections) beyond the LDA or GGA approximations. The most interesting property of this surface system is the large spin splitting of its metallic surface bands and the undulating spin texture along the hexagonal Fermi contours, which highly resembles the spin texture at the Dirac state of the topological insulator Bi2Te3. These properties make this system particularly interesting from both fundamental and technological points of view. [ABSTRACT FROM AUTHOR]

Abstract: We use electronic Raman scattering for studying the band structure of the boron acceptor states in diamond. For the first time, the spin–orbit splitting of these acceptor states and the Lyman series of transitions are observed. The spin–orbit splitting linearly increases with n number. Lyman series exhibit fine structure consisting of four bands each. The energy spacing between series is equal to . Evolution of Raman spectra of the boron-doped diamond with increasing boron concentration is shown. Mott transition is revealed in Raman spectrum. Correct values of Luttinger parameters for diamond are specified. [Copyright &y& Elsevier]

The relativistic two-component complete active space self-consistent field theory in Kramers restricted formalism (KRCASSCF) through the framework of the spin-orbit relativistic effective core potential is implemented into the KPACK package. This paper continues the development previously reported [Y. S. Kim and Y. S. Lee, J. Chem. Phys. 119, 12169 (2003)] and extends the theory by means of adding time-reversal symmetry into the relevant expressions so as to complete the course of theoretical development. We retained the usage of elementary spinor excitation operator for defining the spinor rotation operator and derived the gradient and Hessian in simpler forms than previously found. To eliminate redundant computation resulting from repeating sums in the derivatives, a suitable decomposition method is proposed, which also facilitates the implementation. The two-step near second-order approach is employed for convergence. The present implementation is applicable for both closed- and open-shell systems and is used to calculate the atoms of lower p-block. The results for 5p and 6p are in good agreement with the experiments, and those for 7p are comparable to multi-reference configuration interaction results, showing that KRCASSCF is a versatile tool for the relativistic electronic structure calculation of molecules containing moderate-weight through superheavy elements. [ABSTRACT FROM AUTHOR]

Fermion localization functions are used to discuss electronic and nucleonic shell structure effects in the superheavy element oganesson, the heaviest element discovered to date. Spin-orbit splitting in the 7p electronic shell becomes so large (~ 10 eV) that Og is expected to show uniform-gas-like behavior in the valence region with a rather large dipole polarizability compared to the lighter rare gas elements. The nucleon localization in Og is also predicted to undergo a transition to the Thomas-Fermi gas behavior in the valence region. This effect, particularly strong for neutrons, is due to the high density of single-particle orbitals. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials, especially their most prominent member, graphene, have greatly influenced many scientific areas. Moreover, they have become a base for investigating the relativistic properties of condensed matter within the emerging field of "Dirac physics." This has ignited an intense search for new materials where charge carriers behave as massless or massive Dirac fermions. Here, by the use of density functional theory and symmetry analysis, we theoretically show the existence of Dirac electrons in a series of 2D transition-metal carbides, known as MXenes. They possess eight conical crossings in the first Brillouin zone with giant spin-orbit splitting. Our findings indicate that the 2D band structure of MXenes is protected against external perturbations and preserved even in multilayer phases. These results, together with the broad possibilities to engineer the properties of these phases, make them a potential candidate for studying novel Dirac-physics-based applications. [ABSTRACT FROM AUTHOR]