Herein, a structural shearing behavior in heterolayered (LuFeO3)nLuFe2O4 (n = 0, 1) upon oxygen uptake is reported. Using advanced X-ray and electron diffraction techniques, it is found that when (LuFeO3)nLuFe2O4 absorbs oxygen, only the LuFe2O4 layer is affected, transforming into LuFe2O4.5, while the LuFeO3 layer remains chemically unchanged. Magnetic susceptibility and M & ouml;ssbauer spectroscopy corroborate this local oxygen uptake in the LuFe2O4 layer by confirming the mixed oxidation state of the iron site. Interestingly, even though the LuFeO3 layer in the n = 1 compound does not directly absorb oxygen, it significantly influences how the structure evolves during oxidation. The n = 1 compound (Lu2Fe3O7) is active for oxygen absorption at a lower temperature than the n = 0 compound LuFe2O4 (110 degrees C vs. 150 degrees C from thermal gravimetric measurement). The LuFeO3 layer in Lu2Fe3O7 acts as a buffer zone that reduces strain and chemical pressure within the LuFe2O4 layer thereby enhancing the rate of oxygen absorption. The findings reveal a common behavior in the (LuFeO3)nLuFe2O4 series that provides new insights into the design of ternary oxides active at low temperatures for fast oxygen uptake. This crystallographic study can therefore lead to further improvements in the oxygen storage capability and oxygen absorption rates.

The MnP family of binary compounds presents an intriguingly simple platform to mix-and-match elemental components. Replacement on the transition metal or pnictogen site can alter magnetism, electronic correlations, and electrical properties. Here we report low-temperature properties of CoP, including measurements at magnetic fields exceeding 30 T, revealing de Haas-van Alphen oscillations and a nearly two orders of magnitude increase in resistance. When viewed together with prior work, it is possible to put together a global picture of the role of different atoms in variations in magnetic ordering, lattice coherence, and topological band structure features in this material family.

We have synthesized layered superconducting LiNbO_2 crystals through a bulk phase transformation from LiNbO_3 single crystals via CaH_2 reduction. As the Nb valence is reduced from 5+ to 3+, the material undergoes a structural transformation to the resulting product, LiNbO_2, which is accompanied by metallic behavior and a superconducting transition, Tc onset, as high as 14.4 K. Secondary ion mass spectroscopy (SIMS) and X-ray photoelectron spectroscopy (XPS) show that the resulting phase is hole-doped through de-lithiation during the reduction. Magnetization and AC susceptibility measurements from a tunnel diode resonator confirm the bulk nature of superconductivity with a superconducting volume fraction of approximately 77

Recently, magnetic 2-dimensional (2D) van der Waals (vdW) materials have garnered tremendous attention. The vdW ferromagnet Fe5Ge1Te2 has a Curie temperature Tc of 270 K, which is tailorable by tuning the stoichiometry and the Fe deficiency to reach room temperature. To explore the expanded compositional space, we implemented combinatorial synthesis and high-throughput characterization to investigate the structural phase distribution and ferromagnetism of a Fe-Ge-Te thin film library. The library was prepared by magnetron co-sputtering followed by annealing in vacuum or in an inert environment. Composition and structural phase distribution of the 177 pads in the library were characterized using high-throughput wavelength dispersive spectroscopy (WDS), X-ray diffraction (XRD), and two-point probe resistance measurements. We leverage unsupervised machine learning to cluster the XRD dataset into groups of compositions with similar structural phases, and further study the ferromagnetic properties via SQUID magnetometry and X-ray magnetic circular dichroism (XMCD) across different clusters. The results are compared against magnetization and structural models calculated using DFT. Our results demonstrate that the hexagonal crystal structure is a critical prerequisite for ferromagnetism in this system, and that unexplored materials adopting this structure can be efficiently identified as possible ferromagnetic materials using our high-throughput, ML-assisted framework. This workflow based on the combinatorial strategy allows us to rapidly capture the composition-structure-magnetic property map across a broad compositional landscape of novel magnetic materials.

Chiral materials and multiferroics offer symmetry-controlled electronic and magnetic functionalities, yet their integration in two-dimensional systems remains challenging due to the difficulty of simultaneously sustaining chirality, ferroelectricity, and ferromagnetism at practical temperatures. Here we introduce a chiral molecular intercalation strategy to construct chiral 2D multiferroics by inserting enantiomeric molecules into layered ferroelectric CuInP2S6 and ferromagnetic Fe3GaTe2. Molecular insertion reshapes the interfacial electrostatic environment, induces charge redistribution, and expands the interlayer spacing, resulting in enhanced ferroic order, including a 5-fold increase in magnetic anisotropy energy (0.35→1.6 meV/Fe) and strengthened ferroelectric polarization. The resulting chiral CIPS-FGT heterostructures exhibit robust room-temperature magnetoelectric coupling (∼4.8% magnetization modulation) and enable helicity-dependent control of ferroic states under circularly polarized light, producing a 54.4% resistance modulation. This work establishes molecular intercalation as a general strategy for engineering light-responsive 2D multiferroics for optically tunable magnetoelectric and spintronic devices.

The tetragonal BaAl_4 (I4/mmm) parent structure underpins a diverse family of materials exhibiting novel phenomena, including nematic superconductivity, topological semimetallicity, and heavy fermion behavior. The recent growth of ternary R-Zn-Ga compounds, such as the previously reported CeZn_2Ga_2, has explored some of the members exhibiting rare-earth magnetism within this family. In this paper, we report on the structural and magnetic properties of single crystals of CeZn_2-xGa_2+x, a Ga-rich analogue of CeZn_2Ga_2. Our CeZn_2-xGa_2+x samples exhibit magnetic properties distinct from the paramagnetic behavior previously reported for CeZn_2Ga_2. We observe a magnetic transition around 4 K, pronounced metamagnetic states at low temperatures, and strong magnetic anisotropy. Though there are batch-to-batch variations that suggest a strong sensitivity to local structural imperfections, we consistently see the presence of magnetic transitions and metamagnetic states in our crystals. To investigate the local structural sensitivity hypothesis, we performed Reverse Monte Carlo analysis of collected powder neutron diffraction data, revealing the presence of significant local crystallographic disorder of the magnetic Ce site. Our findings demonstrate that the positional disorder drives competing ferromagnetic and antiferromagnetic correlations that lead to the observed spin glass behavior and complex anisotropic magnetism. This study illustrates that tuning the local crystallographic disorder enables engineering frustrated magnetic states in BaAl_4-type and similar intermetallic structures.

Multiferroics host simultaneous and coupled ferroic orders, allowing disparate external stimuli to induce abrupt transformations in their structures and properties. Creating multiferroicity in two-dimensional (2D) van der Waals (vdW) platforms would add the elements of strong quantum confinement, enhanced quasiparticle excitations, and wide tunability to the capabilities of these systems. In this work, we constructed vdW heterostructures of ferromagnetic triiron gallium ditelluride (Fe3GaTe2) and ferroelectric copper indium thiophosphate (CuInP2S6) to integrate their respective orders. We observed strong interferroic coupling at room temperature by demonstrating ferroelectrically reconfigurable magnetic anisotropy of 2D Fe3GaTe2. The interferroic magnetoelectricity diminished with increasing Fe3GaTe2 thickness, revealing the interfacial nature of heterostructure multiferroicity. Our discovery of all-vdW heterostructure multiferroicity opens the door to the artificial assembly of vdW layers for designer 2D multiferroics.

The crystal and magnetic structures of the nitride antiperovskite Mn_3GeN reveals ferrimagnetic order stemming from a distorted kagome-derived lattice of the Mn atoms. Polycrystalline Mn_3GeN was synthesized via a solid-state reaction and characterized using neutron powder diffraction, DC magnetometry, and first-principles calculations. Rietveld refinement reveals near-stoichiometric composition (Mn_3GeN_0.94(1)) adopting a tetragonal I4/mcm structure at T = 500 K and below, featuring axially distorted and tilted [NMn_6] octahedra that result in a buckled Mn kagome lattice. On heating, the tetragonal distortion and octahedral tilt angle decrease continuously before transitioning to the cubic Pm3̅m antiperovskite phase at T ≈ 524 K. Neutron diffraction and magnetometry together reveal noncollinear ferrimagnetic ordering. For 30 K ≤ T ≤ 500 K, the magnetic structure is described by a single propagation vector, k = (0, 0, 0), with inequivalent Mn1 and Mn2 sublattices that couple antiferromagnetically to yield a net moment. Density functional theory-based calculations show the different local moments originate from the bandwidths associated with the distinct Mn-N bond lengths. The temperature dependence of the sublattice moments indicates a compensation-like crossover between Mn1- and Mn2-derived magnetization near 380 K. These findings uncover a previously unrecognized subtlety in the magnetic and structural behavior of Mn_3GeN, highlighting the interplay between structural distortions, magnetic ordering, and electronic structure in kagome-derived antiperovskite materials.

Intercalated group-V transition metal dichalcogenides (TMD) exhibit a variety of magnetotransport phenomena arising from diverse nuclear and magnetic structures. However, a comprehensive mapping of the magnetic, thermodynamic, and structural phases is lacking. Here, we investigate Co x NbSe2 for x = 0.29-0.36, using quenching and controlled cooling to tune structural order and map the resulting magnetic phases. We find that the altermagnetic states (x = 1/4) and the spin density wave (x = 1/3) remain robust under both synthesis conditions. In contrast, intermediate compositions give rise to spin-glass-like behavior or magnetic phase coexistence, producing two distinct phase diagrams depending on the thermal history of the synthesis process. To identify the underlying drivers of each ground state, we applied reverse Monte Carlo modeling to diffuse neutron scattering data, revealing the presence of local 3 a h x 3 a h sublattice domains in all samples independently of the synthesis conditions. As the intercalant concentration decreases, the Co ions preferentially adopt the 2a h x 2a h sublattice, where dominant magnetic interactions emerge, stabilizing the altermagnetic phase. We evaluated these interactions through first-principles calculations for x = 1/4 and 1/3, where each domain interaction type is structurally and magnetically well-defined. The resulting exchange reveals spin-glass and spin density wave phases driven by frustration from tighter intercalant arrangement and altermagnetism from 2a h x 2a h domains. Overall, we present local structure-driven magnetic phases across Co x NbSe2 compositions, demonstrating how synthesis impacts local order of the Co atoms and thereby the overall magnetic properties.

We present a comprehensive study of the nuclear and magnetic structures of the mixed olivine solid solution series LiFe1-xCoxPO4 as well as their delithiated counterparts, for metal concentrations x = 0.2-0.6. Through neutron powder diffraction studies, we find that the LiFe1-xCoxPO4 series orders in the magnetic space group Pnma ', consistent with their Li(Fe/Co)PO4 parent structures. After chemical delithiation using peracetic acid, however, the removal of over 30% of the lithium from the lattice results in a transition from an Ay-type to an Ax-type antiferromagnetic structure. The magnetic space group consistent with Ax antiferromagnetism was found to be Pn ' m ' a '. Interestingly, magnetic susceptibility measurements of both series reveal that delithiation increases the magnetic transition temperature, TN, from 50 K to 115 K. We find through analysis of the diffraction data that the unit cell parameters change linearly as a function of x; consequently, the exchange pathways between the Fe/Co magnetic cations are affected by the delithiation. We discuss how exchange pathways, metal oxidation states, and d-orbital occupation all contribute to the observed magnetic symmetries and trends in TN in both series.

The van der Waals material Fe3GaTe2 is known to exhibit long-range ferromagnetism above room temperature, making it highly attractive for potential two-dimensional spintronic applications. Using a combination of single crystal X-ray diffraction, powder X-ray diffraction, and neutron diffraction, we report that Fe3GaTe2 is best described as a self-intercalated ferrimagnet with interstitial iron sites that stabilize its long-range magnetic order at high temperatures. We find the amount of interstitial sites to vary between 7% and 11%, and its total moment to be approximately 1.6(6)mu B at 1.5 K by neutron diffraction analysis; the other two iron sites have total moments of 0.7(2)mu B and 1.65(6)mu B at base temperature. Group theory analysis reveals that only one magnetic space group is consistent as the maximal isomorphic subgroup of the parent paramagnetic group P63/mmc. The resulting magnetic space group of P63/mm ' c ' leads to a collinear antiferromagnetic arrangement of the interstitial iron sites with respect to those in the telluride layers and with the iron moments all out of plane. Through DFT studies based on the experimental crystal structure, we find that the ferrimagnetic state is favorable over that of the ferromagnetic state by 66 meV. The calculated band structures for the ferromagnetic and ferrimagnetic models show that a significant re-distribution of the electronic density of states occurs near the Fermi level due to the presence of the antiferromagnetically coupled interstitial iron.

We use a combination of crystallographic data mining methods, structural diagrams, and chemical design rules to search for existing solid-state two-dimensional (2D) functional materials such as the van der Waals ferroelectric (vdW FE) CuInP2S6 and then use this to predict which combinations of elements might result in similar architectures. The design rules rely on previously published structural information, from a combination of curated database and online literature searches, and are used to create a set of crystallographic quantum structural diagrams (QSDs) to determine the optimal phase spaces required for 2D vdW phosphochalcogenides. We propose that a search within specific phase spaces will result in combinations of elements that represent unexplored examples of solid-state 2D vdW ferroics. The design rules presented here rely on materials parameters like radii, electronegativity, valence electron count, and melting point, which are common in solid-state inorganic chemistry. This paper culminates with the data-guided prediction of 83 potentially synthesizable 2D vdW phosphochalcogenides, of which our preliminary combination of density functional theory (DFT), synthesis, and single-crystal analysis of bulk 2D vdW materials points toward a clear path where a wealth of materials can be created and ultimately exhibit useful properties like (anti)ferroelectricity.

In CoxNbSe2, crystal symmetry and cobalt site occupation drive the formation of two distinct magnetic phases. At x = 1/4, the centrosymmetric structure (P63/mmc) promotes Co-Co interactions leading to the formation of an A-type antiferromagnetic structure phase with a transition temperature of TNA = 169 K. At x = 1/3, the noncentrosymmetric structure (P6322) induces a lower-temperature magnetic phase with TNS = 28 K. We report the coexistence of both substructures within a superlattice, with a nuclear propagation vector of (1/3, 1/3, 0) relative to the host lattice. Single crystals of Co0.28NbSe2 exhibit both magnetic transitions, with TNA corresponding to the x <^> 1/4 phase and TNS corresponding to the x <^> 1/3 phase. Magnetic susceptibility and specific heat measurements confirm these transitions, although only the high-temperature TNA phase significantly affects resistivity. We successfully isolate each phase in powder samples, while single crystals with an intercalation ratio of x = 0.28 display the coexistence of both phases in a single sample. Using single-crystal neutron diffraction, we solved the magnetic structure of the high-temperature centrosymmetric phase (TNA), and neutron powder diffraction revealed the double-q magnetic structure of the low-temperature noncentrosymmetric phase (TNS).

Intercalated group-V transition metal dichalcogenides (TMD) exhibit a variety of magnetotransport phenomena arising from diverse nuclear and magnetic structures. However, a comprehensive mapping of the magnetic, thermodynamic, and structural phases is lacking. Here, we investigate CoxNbSe2 for x = 0.29-0.36, using quenching and controlled cooling to tune structural order and map the resulting magnetic phases. We find that the altermagnetic states (x = 1/4) and the spin density wave (x = 1/3) remain robust under both synthesis conditions. In contrast, intermediate compositions give rise to spin-glass-like behavior or magnetic phase coexistence, producing two distinct phase diagrams depending on the thermal history of the synthesis process. To identify the underlying drivers of each ground state, we applied reverse Monte Carlo modeling to diffuse neutron scattering data, revealing the presence of local 3ah×3ah sublattice domains in all samples independently of the synthesis conditions. As the intercalant concentration decreases, the Co ions preferentially adopt the 2ah× 2ah sublattice, where dominant magnetic interactions emerge, stabilizing the altermagnetic phase. We evaluated these interactions through first-principles calculations for x = 1/4 and 1/3, where each domain interaction type is structurally and magnetically well-defined. The resulting exchange reveals spin-glass and spin density wave phases driven by frustration from tighter intercalant arrangement and altermagnetism from 2ah× 2ah domains. Overall, we present local structure-driven magnetic phases across CoxNbSe2 compositions, demonstrating how synthesis impacts local order of the Co atoms and thereby the overall magnetic properties.

Herein, a structural shearing behavior in heterolayered (LuFeO 3 ) n LuFe 2 O 4 ( n = 0, 1) upon oxygen uptake is reported. Using advanced X‐ray and electron diffraction techniques, it is found that when (LuFeO 3 ) n LuFe 2 O 4 absorbs oxygen, only the LuFe 2 O 4 layer is affected, transforming into LuFe 2 O 4.5 , while the LuFeO 3 layer remains chemically unchanged. Magnetic susceptibility and Mössbauer spectroscopy corroborate this local oxygen uptake in the LuFe 2 O 4 layer by confirming the mixed oxidation state of the iron site. Interestingly, even though the LuFeO 3 layer in the n = 1 compound does not directly absorb oxygen, it significantly influences how the structure evolves during oxidation. The n = 1 compound (Lu 2 Fe 3 O 7 ) is active for oxygen absorption at a lower temperature than the n = 0 compound LuFe 2 O 4 (110 °C vs. 150 °C from thermal gravimetric measurement). The LuFeO 3 layer in Lu 2 Fe 3 O 7 acts as a buffer zone that reduces strain and chemical pressure within the LuFe 2 O 4 layer thereby enhancing the rate of oxygen absorption. The findings reveal a common behavior in the (LuFeO 3 ) n LuFe 2 O 4 series that provides new insights into the design of ternary oxides active at low temperatures for fast oxygen uptake. This crystallographic study can therefore lead to further improvements in the oxygen storage capability and oxygen absorption rates.

The design of heterostructures provides a promising avenue for discovering and manipulating emergent quantum phenomena within correlated electron systems. This approach is particularly relevant for iron-based chalcogenides, such as superconducting FeSe, whose properties can be tuned with different intercalates. We report the hydrothermal synthesis of a family of layered double hydroxide (LDH) intercalated iron chalcogenides, [Mg1-xAlx(OH)2]Fe1-yS and [M1-xAlx(OD)2]Fe1-ySe (M = Mg, Mn, Fe), with x, y < 0.33. We introduce the Mn-containing selenide as a new member, synthesized hydrothermally, broadening the accessible compositional range. We previously reported some details of the synthesis of the Mg- and Fe-based analogues; here, we provide new structural insights obtained through combined selected-area electron diffraction, neutron and X-ray powder diffraction, and pair distribution function analysis. Selected-area electron diffraction of the sulfide analogue reveals a strongly modulated supercell with 2-fold symmetry, consistent with the mineral tochilinite. In contrast, the selenide analogue largely preserves tetragonal symmetry with weak superlattice reflections from subtle periodic modulation or ordering. Guided by electron diffraction, neutron scattering, and PDF analysis, we construct and validate a new FeSe-LDH heterolayer model that retains 4-fold symmetry. This study strengthens the current structural understanding of these lesser-known intercalated iron chalcogenide misfit heterostructures.

A Pt(II) aqua complex 5 MSN supported by mesoporous silica nanoparticle (MSN)-immobilized sulfonated CNN pincer ligand featuring a rigid SiO3 tether was prepared. This hybrid material was tested as a catalyst in H/D exchange reactions of C(sp2)-H bonds of selected aromatic substrates and D2O-2,2,2-trifluoroethanol-d 1 (TFE-d 1) mixtures or CD3CO2D acting as a source of exchangeable deuterium. The catalyst immobilization served as a means to not only enable the catalyst's recyclability but also minimize the coordination of sulfonate groups and the metal centers originating from different catalyst's moieties that would preserve reactive PtII(OH2) fragments needed for catalytic C-H bond activation. In the same vein, the use of a rigid tether was expected to help suppress potentially strong intraparticle coordination of MSN's silanol groups and Pt(II) that could inhibit the catalytic H/D exchange. The particle size distribution, porosity, surface area, elemental composition of 5 MSN , and the pincer ligand loading were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX) analysis, N2 sorption, and alkaline digestion with subsequent 1H NMR and ESI-MS analyses of the resulting solutions. It was found that 5 MSN is a more active catalyst of the H/D exchange reactions of benzene, thiophene, anisole, and/or toluene than analogous molecular Pt(II) aqua complexes 1 and 5, which exhibited 2-10 times lower TON after 24 h of reaction under otherwise identical conditions. The greater activity and chemical robustness of 5 MSN allowed us to effectively use the catalyst in the H/D exchange reactions with acetic acid-d 4, which is a more readily available source of exchangeable deuterium than TFE-d 1 at 120 degrees C. The recyclability of 5 MSN was also demonstrated.

We synthesized LuMnGaO4, an AB2O4-type compound, and performed structural analysis and characterization focusing on its reversible oxygen uptake and oxidation-driven color change. The reduced phase, LuMnGaO4, synthesized via solid-state reactions, crystallizes in the R3m space group. Heating this metal oxide in an oxygen-rich environment induces a phase transition to the oxidized phase, LuMnGaO4.5, which adopts the P3 space group. Through neutron diffraction studies, we elucidate the structural transition upon oxygen uptake, while in situ synchrotron X-ray powder diffraction confirms a low temperature (similar to T = 250 degrees C) transition. The oxidation process induces a significant color shift from greenish-grey to black, and we quantify this electronic transition by UV-visible spectroscopy. Electron diffraction and synchrotron X-ray data further reveal structural modulations in the form of superlattice reflections and diffuse scattering associated with oxygen disorder in the oxidized phase. The diffraction data show that the reversible oxygen uptake and release occurs in the bulk phase at relatively low temperatures, suggesting applications in oxygen transport technologies. Furthermore, the distinct color change highlights its potential as a bifunctional material for oxygen carriers and colorimetric oxygen sensors. This work provides a foundation for future exploration of the structural and electronic evolution of AB2O4-type compounds during oxygen uptake and release.