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Abstract The interaction between strong correlation and Berry curvature is an open territory of in the field of quantum materials. Here we report large anomalous Hall conductivity in a Kondo lattice ferromagnet USbTe which is dominated by intrinsic Berry curvature at low temperatures. However, the Berry curvature induced anomalous Hall effect does not follow the scaling relation derived from Fermi liquid theory. The onset of the Berry curvature contribution coincides with the Kondo coherent temperature. Combined with ARPES measurement and DMFT calculations, this strongly indicates that Berry curvature is hosted by the flat bands induced by Kondo hybridization at the Fermi level. Our results demonstrate that the Kondo coherence of the flat bands has a dramatic influence on the low temperature physical properties associated with the Berry curvature, calling for new theories of scaling relations of anomalous Hall effect to account for the interaction between strong correlation and Berry curvature. 

A new compound, Ba 3 Ga 2 O 5 Cl 2 , isostructural with Ba 3 Fe 2 O 5 Cl 2 , was synthesized by solid-state reaction in air. Through single-crystal and powder X-ray diffraction analysis, the crystal structure was determined to be cubic with chiral space group I 2 1 3 and unit-cell parameter a  = 9.928 (1) Å. The Ga 3+ ions in Ba 3 Ga 2 O 5 Cl 2 are coordinated by O atoms and form GaO 4 tetrahedra. Ten neighboring GaO 4 tetrahedra are further bridged through corner sharing and rotation along the body diagonal, producing the chiral structure. Magnetization measurements indicate temperature-independent diamagnetic behavior, which is qualitatively consistent with core diamagnetism from all the constituent elements. 

Van der Waals ferromagnets are thrilling materials from both a fundamental and technological point of view. VI3 is an interesting example, with a complex magnetism that differentiates it from the first reported Cr based layered ferromagnets. Here, we show in an indirect way through angle resolved photoemission spectroscopy experiments, the importance of spin–orbit coupling setting the electronic properties of this material. Our light polarized photoemission measurements point to a ground state with a half-filled e±′ doublet, where a gap opening is triggered by spin–orbit coupling enhanced by electronic correlations.

 

The synthesis, crystal structure determination, magnetic properties and bonding interaction analysis of a novel 3 d transition-metal complex, [CrBr 2 (NCCH 3 ) 4 ](Br 3 ), are reported. Single-crystal X-ray diffraction results show that [CrBr 2 (NCCH 3 ) 4 ](Br 3 ) crystallizes in space group C 2/ m (No. 12) with a symmetric tribromide anion and the powder X-ray diffraction results show the high purity of the material specimen. X-ray photoelectron studies with a combination of magnetic measurements demonstrate that Cr adopts the 3+ oxidation state. Based on the Curie–Weiss analysis of magnetic susceptibility data, the Néel temperature is found to be around 2.2 K and the effective moment (μ eff ) of Cr 3+ in [CrBr 2 (NCCH 3 ) 4 ](Br 3 ) is ∼3.8 µ B , which agrees with the theoretical value for Cr 3+ . The direct current magnetic susceptibility of the molecule shows a broad maximum at ∼2.3 K, which is consistent with the theoretical Néel temperature. The maximum temperature, however, shows no clear frequency dependence. Combined with the observed upturn in heat capacity below 2.3 K and the corresponding field dependence, it is speculated that the low-temperature magnetic feature of a broad transition in [CrBr 2 (NCCH 3 ) 4 ](Br 3 ) could originate from a crossover from high spin to low spin for the split d orbital level low-lying states rather than a short-range ordering solely; this is also supported by the molecular orbital diagram obtained from theoretical calculations. 

Subtle visual manipulations to the presentation of mathematical notation influence the way that students perceive and solve problems. While there is a consistent impact of perceptual cues on students’ problem-solving, other cognitive skills such as inhibitory control may interact with perceptual cues to affect students’ arithmetic problem-solving performance. We present an online experiment in which college students completed a version of the Stroop task followed by arithmetic problems in which the spacing between numbers and operators was either congruent (e.g., 2 + 3×4) or incongruent (e.g., 2+3 × 4) to the order of precedence. We found that students were comparably accurate between problem types but might have spent longer responding to problems with congruent than incongruent spacing. There was no main effect of inhibitory control on students’ performance on these problems. However, an exploratory analysis on a combined performance measure of accuracy and response time revealed an interaction between problem type and inhibitory control. Students with higher inhibitory control performed better on congruent versus incongruent problems, whereas students with lower inhibitory control performed worse on congruent versus incongruent problems. Together, these results suggest that the relation between inhibitory control and arithmetic performance may not be straightforward. Furthermore, this work advances perceptual learning theory and contributes new findings on the contexts in which perceptual cues, such as spacing, influence arithmetic performance.

 

The results of the structural determination, magnetic characterization, and theoretical calculations of a new ruthenium-oxo complex, Li 4 [Ru 2 OCl 10 ]·10H 2 O, are presented. Single crystals were grown using solvent methods and the crystal structure was characterized by single crystal X-ray diffraction. Li 4 [Ru 2 OCl 10 ]·10H 2 O crystallizes into a low-symmetry triclinic structure ( P 1 ) due to the much smaller Li + cation compared to K + cation in the tetragonal complex K 4 [Ru 2 OCl 10 ]·H 2 O. The X-ray photoelectron spectra confirm only the single valent Ru 4+ in Li 4 [Ru 2 OCl 10 ]·10H 2 O even though two distinct Ru sites exist in the crystal structure. Magnetic measurements reveal the diamagnetic property of Li 4 [Ru 2 OCl 10 ]·10H 2 O with unpaired electrons existing on Ru 4+ . Furthermore, the molecular orbital analysis matches well with the observed UV and magnetic measurements. 

Informed by a constructivist-based, student-adaptive pedagogical approach, this study explores the benefits of teacher–learner discourse moves for the mathematics learning of students with learning disabilities (LD). During a constructivist teaching experiment for nurturing the multiplicative reasoning and problem solving of five third-grade students with school-identified LD, we analyzed the global trends and detailed dynamics of teacher–student interactions with statistical discourse analysis. We found that the teacher’s discourse moves to support each individual student’s problem solving helped engage them in mathematical reasoning, which improved their problem-solving performance. Thus, this study contributes to knowledge in the field of special education by (a) specifying ways in which discourse-oriented mathematics instruction can help each student with LD and (b) showcasing a novel statistical analysis of teacher–student discourse.