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Three new double corundum derived compounds, Fe3-xInSnxO6, (x = 0. 0.25, 0.5) were synthesized at high pressure and temperature (6 GPa, 1400-1450 C) All the compounds order antiferromagnetically well above room temperature, TN = 608 K, 532K, and 432 K for x = 0, 0.25, 0.5, respectively. The x = 0 phase crystalizes as centrosymmetric R3c, but increasing the substitution of closed-shell d10 Sn4+ induces x = 0.25 and 0.5 to crystallize as noncentrosymmetric R3c. Microprobe measurements indicate that for x = 0.25, 0.5, the substitution of Sn4+ is not compensated for by vacancies, which implies the presence of Fe2+, as corroborated by X-ray absorption near edge spectroscopy and single crystal X-ray structure refinements. Neutron powder diffraction experiments on x = 0.5 indicate that, these compounds are canted A-type antiferromagnets which, like Fe2O3 and InFeO3, consist of ferromagnetic layers that stack antiferromagnetically with a single magnetic transition. Weak ferromagnetic interactions persist to very high temperatures. Temperature dependent second harmonic generation measurements on x = 0.25 and 0.5 show SHG response with ferroelectric-like hysteretic maxima that correspond with the respective magnetic transitions, which suggest coupling of the magnetic and polarization order. These new compounds provide more information on fine-tuning the electronic, magnetic and structural properties of corundum derived mutlferroics in the search for tunable high temperature magnetoelectric materials.

We study near-neighbour and dipolar Ising models on a lattice of corner-sharing octahedra. In an extended parameter range of both models, frustration between antiferromagnetism and a spin-ice-like three-in-three-out rule stabilises a Coulomb phase with correlated dipolar and quadrupolar spin textures, both yielding distinctive neutron-scattering signatures. Strong further-neighbour perturbations cause the two components to order independently, resulting in unusual multi-$k$ orders. We propose experimental realisations of our model in rare-earth antiperovskites., 6+10 pages, 5+5 figures with supplementary text; ancillary mcif files illustrate the ordered phases

The magnetic structure of NaYMnWO6 was determined by neutron powder diffraction measurements. Below 9 K, the magnetic structure is a helix to wave vector k = (0, 0.447, 1/2), in contrast with NaYNiWO6, which shows a transverse spin density wave with k = (0.47, 0, 0.49). By analyzing the differences in the spin exchanges of NaYMnWO6 and NaYNiWO6, and in the magnetic anisotropies of the Mn2+ (d5, S = 5/2) and the Ni2+ (d2, S = 1) ions, we show what factors govern the propagation direction of a noncollinear magnetic structure and whether it becomes a helix or a cycloid.

In the following paper, the possibility of using fruit tree species, including minor fruit trees, in an urban area of Perugia (Italy), was represented, considering their possible productive, ecosystem and economic contribution. The simulated food forest, created through the use of a web app, can be regarded as an "organic green area" in which different fruit trees grow without resorting to the use of synthetic chemicals, respecting the ecosystem and minimizing soil exploitation. Among the four chosen species (Arbutus unedo, Morus nigra, Prunus avium, Ficus carica), both Ficus carica and Morus nigra showed good potential fruit production and storage of CO2 from the environment, in particular, the species Morus nigra had the highest potential economic value, considering fruit selling in a 50-year time frame.

Funding: A. W. R. and A. S. G. were supported by the Engineering and Physical Sciences Research Council (grant numbers EP/P024564/1 and EP/T011130/1 respectively). This work has been supported in part by the Alexander von Humboldt Foundation. The band topology of magnetic semimetals is of interest both from the fundamental science point of view and with respect to potential spintronics and memory applications. Unfortunately, only a handful of suitable topological semimetals with magnetic order have been discovered so far. One such family that hosts these characteristics is the antiperovskites, A3BO, a family of 3D Dirac semimetals. The A=Eu2+ compounds magnetically order with multiple phases as a function of applied magnetic field. Here, by combining band structure calculations with neutron diffraction and magnetic measurements, we establish the antiperovskite Eu3PbO as a new topological magnetic semimetal. This topological material exhibits a multitude of different topological phases with ordered Eu moments which can be easily controlled by an external magnetic field. The topological phase diagram of Eu3PbO includes an antiferromagnetic Dirac phase, as well as ferro- and ferrimagnetic phases with both Weyl points and nodal lines. For each of these phases, we determine the bulk band dispersions, the surface states, and the topological invariants by means of ab initio and tight-binding calculations. Our discovery of these topological phases introduces Eu3PbO as a new platform to study and manipulate the interplay of band topology, magnetism, and transport. Publisher PDF

A Polycrystalline sample of Pb2NiOsO6 was synthesized by high-pressure (6 GPa) and high-temperature (1575 K) conditions. Pb2NiOsO6 crystallizes in a monoclinic double perovskite structure with a centrosymmetric space group P21/n at room temperature. Pb2NiOsO6 is metallic down to 2 K and shows a single antiferromagnetic (AFM) transition at TN = 58 K. Pb2NiOsO6 is a new example of a metallic and antiferromagnetic oxide with three-dimensional connectivity. Neutron powder diffraction and first-principle calculation studies indicate that both Ni and Os moments are ordered below TN and the antiferromagnetic magnetic order breaks inversion symmetry. This loss of inversion symmetry driven by antiferromagnetic order is unusual in metallic systems and the 3d-5d double-perovskite oxides represent a new class of noncentrosymmetric AFM metallic oxides.

We report the structural, magnetic, and electrical properties of a new family of doubly ordered perovskites NaLnNiWO6 (Ln = La, Pr, Nd, Sm, Eu, Gd, and Tb), synthesized at high-pressure (4.5 GPa) and high-temperature (1000 °C) conditions. These materials crystallize in the monoclinic structure with the polar space group P21 as revealed by neutron diffraction (Ln = La), X-ray diffraction, and second-harmonic-generation (SHG) studies. These compounds exhibit a combined layered ordering of A-site cations and rock-salt ordering of B-site cations with octahedral tilting, which breaks the inversion symmetry and results in a polar structure. The magnetic and heat capacity measurements reveal the antiferromagnetic order of Ni2+ ion moments in the temperature range of 23–30 K, depending on the Ln ion. Analysis of neutron powder diffraction data for the La compound reveals that the Ni2+ spins couple antiferromagnetically along the a- and c-directions and ferromagnetically along the b-axis, consistent with the propagation vector, k = (1/2, 0, 1/2). In contrast to the compounds with smaller lanthanide ions (Ln = Y, Dy, Ho, and Yb), these compounds do not exhibit measurable electric polarization at TN but show a dielectric anomaly.

Understanding structural responses of metal–organic frameworks (MOFs) to external stimuli such as the inclusion of guest molecules and temperature/pressure has gained increasing attention in many applications, for example, manipulation and manifesto smart materials for gas storage, energy storage, controlled drug delivery, tunable mechanical properties, and molecular sensing, to name but a few. Herein, neutron and synchrotron diffractions along with Rietveld refinement and density functional theory calculations have been used to elucidate the responsive adsorption behaviors of defect-rich Zr-based MOFs upon the progressive incorporation of ammonia (NH3) and variable temperature. UiO-67 and UiO-bpydc containing biphenyl dicarboxylate and bipyridine dicarboxylate linkers, respectively, were selected, and the results establish the paramount influence of the functional linkers on their NH3 affinity, which leads to stimulus-tailoring properties such as gate-controlled porosity by dynamic linker flipping, disorder, and structural rigidity. Despite their structural similarities, we show for the first time the dramatic alteration of NH3 adsorption profiles when the phenyl groups are replaced by the bipyridine in the organic linker. These molecular controls stem from controlling the degree of H-bonding networks/distortions between the bipyridine scaffold and the adsorbed NH3 without significant change in pore volume and unit cell parameters. Temperature-dependent neutron diffraction also reveals the NH3-induced rotational motions of the organic linkers. We also demonstrate that the degree of structural flexibility of the functional linkers can critically be affected by the type and quantity of the small guest molecules. This strikes a delicate control in material properties at the molecular level.

We have investigated magneto-structural phase transitions in polycrystalline YVO3 using high-resolution neutron powder diffraction toward understanding the phenomenon of magnetization reversal. Contrary to earlier reports, our study reveals that both C-type and G-type antiferromagnetic ordering, corresponding to G-type and C-type orbital ordered phases, respectively, occur at the same temperature (TN = 115 K) with the G-type antiferromagnetic phase growing at the expense of the C-type one on cooling. These processes cease at TS ∼ 77 K; however, a minor (∼4%) untransformed C-type phase remains unchanged down to 1.7 K. The symmetry analysis indicates different symmetry origins of the Dzyaloshinskii-Moriya interaction in each phase, which can explain the magnetization reversal observed between TN and TS. We discuss that magnetic phase separation and associated weak ferromagnetism may be the common mechanism underlying the magnetization reversal phenomenon observed in other RVO3 systems (R = rare earth).

The incommensurate magnetic structure (0.47, 0, 0.49) of NaYNiWO6 exhibits unconventional spin-density waves (SDWs) along the [100] direction, in which up and down spins alternate in each half-wave. This is in contrast to conventional SDWs, in which only one type of spin is present in each half-wave. We probed the formation of these unconventional SDWs by evaluating the spin exchanges of NaYNiWO6 based on density functional theory calculations and analyzing the nature of the spin frustration in NaYNiWO6 and by noting that a SDW is a superposition of two cycloids of opposite chirality. The unconventional SDWs along the [100] direction originate from the spin-frustrated antiferromagnetic chains of Ni2+ ions along that direction, leading to conventional SDWs along the [101] direction and unconventional SDWs along the [001] direction.

Multiferroics, showing the coexistence of two or more ferroic orderings at room temperature, could harness a revolution in multifunctional devices. However, most of the multiferroic compounds known to date are not magnetically and electrically ordered at ambient conditions, so the discovery of new materials is pivotal to allow the development of the field. In this work, we show that BaFe

The solid solution Pb1-xSrxMnBO4 is reported with an orthorhombic, Pnma, structure throughout; here studies on compounds with x = 0, 0.5 and 1 are described. The structure contains chains of MnO6 octahedra that exhibit intra-chain ferromagnetic (FM) order at low temperatures. Neutron powder diffraction (NPD) reveals dominant FM order in PbMnBO4 (Tc = 30 K), whereas SrMnBO4 is primarily antiferromagnetic (AFM) with TN = 16 K; the difference is related to the link between the chains that involves the BO3 groups. PbMnBO4 has its moment along a but also has a previously unreported AFM contribution along c (magnetic space group Pnm'a'), whereas SrMnBO4 has its moment along a but also a FM canting along c (magnetic space group Pn'm'a). The end members show distinct magnetostriction at Tc/TN which correlates with the different magnetic exchange in these compounds. NPD in variable applied magnetic field shows that SrMnBO4 is converted to fully FM at 8 T. The behavior above the magnetic ordering temperature is consistent with short-range FM correlations within the chains, which is particularly apparent in PbMnBO4. The magnetocaloric effect (MCE) has been measured and compared with those previously reported for the mineral gaudefroyite. PbMnBO4 has excellent MCE behavior, especially near Tc, 30 K. The strong FM exchange within the chains and FM correlations above Tc are vital for the MC properties.

Classification schemes for reporting thyroid cytology of fine needle aspiration (FNA) of thyroid nodules are largely used in clinical practice, but the level of inter-observer agreement among cytopathologists is poorly acknowledged. The present study aimed to explore the inter-observer agreement among the experienced authors of the 2014 Italian Consensus for Classification and Reporting of Thyroid Cytology (ICCRTC). A stratified randomization was performed in order to obtain a sample homogeneously distributed and representative of all ICCRTC classes. Four high-experience raters were randomly selected among the extensors of the Italian consensus. They independently reviewed 60 FNA samples blindly of the initial cytological report and clinical features. Their overall agreement was evaluated according to Fleiss' kappa. The overall inter-observer agreement was moderate (κ 0.46). Specifically, a good agreement was found when the samples were consistent for malignancy (TIR5) or were not adequate for diagnosis (TIR1) (κ 0.67 and κ 0.73, respectively). A moderate agreement was present for suspicious-for-malignant category (TIR4), and a fair agreement was recorded in the two intermediate ones (TIR3A and TIR3B) (κ 0.36 and κ 0.35, respectively). For clinical purposes, the agreement was good (κ 0.74) in differentiating cases with surgical indication (TIR4/TIR5) from those in which surgery is not essential or requires limited extension (TIR3B/TIR3A/TIR2). In conclusion, the present study confirms the reliability of ICCRTC. These data represent a reference for cytopathologists using this system and are useful for the practice of clinicians and surgeons.

Octahedral distortion in ABO3 perovskite materials is ubiquitous because of the ionic size mismatch between A and B cations, leading to various kinds of crystal symmetry. However, such a distortion always results in centrosymmetric structures except for the covalent bond formation because of the second-order Jahn–Teller (SOJT) effect that occurs with d0 or lone-pair cations. Here, we report that an unusual combination of the layered A-site cation ordering and B-site rock salt ordering in NaYNiWO6 prepared under high-pressure and high-temperature conditions results not only in a polar (P21) structure, as revealed by the neutron diffraction analysis, but exhibits multiferroic properties below the magnetic ordering of Ni2+ ions (TN = 21 K). Analysis of the neutron diffraction data at 20 K reveals an incommensurate sinusoidal spin ordering with the propagation vector, ki = (0.471(2), 0, 0.491(4)), and a commensurate collinear spin structure with kc = (0.5, 0, 0.5) below 18 K. X-ray diffraction data confirm the polar structure in Dy, Ho, and Yb compounds. All four compounds exhibit a switchable change in electric polarization (ΔP) at the magnetic ordering temperatures, demonstrating coupling between ferroelectricity and magnetism.

The double perovskite Ba2CoOsO6, synthesized using solid-state methods at ambient pressure, is shown as a rare example of an oxide adopting the 6L-trigonal (S.G.: P3m1) perovskite structure. The s...

Probing the magnetic structure of magnetocaloric materials in applied fields, can reveal detailed insight into the mechanism of magnetic refrigeration thereby linking the magnetic states that form under applied magnetic fields to changes in magnetic entropy. This study probes the long range magnetic order in \(Tb(DCO_2)_3\) and \(TbODCO_3\) as a function of temperature and applied magnetic field, through neutron diffraction measurements. A triangular Ising antiferromagnetic phase is formed, in small applied magnetic fields in \(Tb(DCO_2)_3\), a spin flip transition occurs to a simple ferromagnetic structure in higher applied fields. \(TbODCO_3\) undergoes a phase transition, in applied fields, into two magnetic phases; namely a buckled chain ferromagnetic phase along the b-axis and a canted antiferromagnetic phase, with a ferromagnetic component along c-axis. Both of the states observed in \(TbODCO_3\) are consistent with Ising-like anisotropy previously reported in \(TbODCO_3\) and the coexistance of these is likely the result of applying a magnetic field to a powdered sample.

According to previous theoretical work, the binary oxide CuO can become a room-temperature multiferroic via tuning of the superexchange interactions by application of pressure. Thus far, however, there has been no experimental evidence for the predicted room-temperature multiferroicity. Here, we show by neutron diffraction that the multiferroic phase in CuO reaches 295 K with the application of 18.5 GPa pressure. We also develop a spin Hamiltonian based on density functional theory and employing superexchange theory for the magnetic interactions, which can reproduce the experimental results. The present Letter provides a stimulus to develop room-temperature multiferroic materials by alternative methods based on existing low temperature compounds, such as epitaxial strain, for tunable multifunctional devices and memory applications.

Hemp (Cannabis sativa) is a well-known crop with a great potential to produce fibers without being excessively water and nutrient demanding. Moreover, hemp can be considered a viable and sustainable alternative to reach a cleaner production in the garment industry. Accurate information on fiber traits will enhance the exploitation of hemp in textile and biofuel industry. The aim of this work was to investigate the cyto-histological characteristics of hemp primary and secondary fibers through semi-thin sections and a light microscopy approach. To this purpose, we cultivated in open field a dioecious hemp variety under two different sowing densities and two different fertilization regimes. We confirmed the prominent role of sex in influencing all the analyzed traits; moreover, we found the possibility to mitigate it by changing the sowing density and the fertilization regime. In particular, the cell wall thickening in primary fibers was reduced in female plants by high fertilization. In male plants, combining high fertilization and low density, secondary fibers development is deeply increased. Cell area, in both plant sexes, was reduced by high fertilization. Operating on these simple agronomic aspects could thus result in the desired amount of fibers/lignin, depending on the final purpose of hemp cultivation.

Even if the sensitivity of vegetation phenology to climate change has been accepted on global and continental scales, the correlation between global warming and phenotypic variability shows a modulated answer depending on altitude, latitude, and the local seasonal thermal trend. To connect global patterns of change with local effects, we investigated the impact of the observed signal of warming found in Central Italy on two different willow species, Salix acutifolia and Salix smithiana, growing in three phenological gardens of the International Phenological Gardens’ network (IPG) located in different orographic positions. The time series of temperatures and phenological data for the period 2005–2018 were analysed first to find trends over time in the three gardens and then to correlate the recent local warming and the change in the two species phenology. The results confirmed the correlation between phenological trends and local trend of temperatures. In particular: budburst showed a trend of advancement of 1.4 days/year on average in all three gardens; flowering showed a divergent pattern between the gardens of either advancement of 1.0 days/year on average or delay of 1.1 days/year on average; while senescence showed a delay reaching even 3.3 days/year, although significant in only two gardens for both species. These trends were found to be correlated mainly with the temperatures of the months preceding the occurrence of the phase, with a shift in terms of days of the year (DOY) of the two species. Our conclusion is that the observed warming in Central Italy played a key role in controlling the phenophases occurrences of the two willow species, and that the orographic forcing leads to the different shift in DOY of phenophases (from 5 to 20 days) due to the local thermal forcing of the three phenological gardens.

The objective of this work was to investigate the potential ecosystem services of 16 fruit trees to plan and manage more efficiently “Urban Forest,” increasing also the resilience of cities to climate change. We evaluated the potential capacity of PM10 absorption, the storage of CO2 from the atmosphere, and the cooling of the environment through shading by the crown and through evapotranspiration. We observed that some species, such as Morus nigra, Juglans regia, Pyrus communis, and Cydonia oblonga, are able to store a higher quantity of CO2 than others over a period of 50 years, respectively, of 2.40 tons, 2.33 tons, 1.51 tons, and 0.96 tons. Ficus carica, Juglans regia, and Morus nigra were relevant for PM10 absorption, since they were able to absorb, referring to the year 2019, 146.4 gr/tree, 195.6 gr/tree, and 143.1 gr/tree, respectively. Results showed that these ecosystem functions depend principally on the morphological characteristics of the individuals: their height, DBH, expansion of their crowns, and characteristics of the foliage system.

$\mathrm{Ce}{\mathrm{Rh}}_{6}{\mathrm{Ge}}_{4}$ is an unusual example of a stoichiometric heavy fermion ferromagnet, which can be cleanly tuned by hydrostatic pressure to a quantum critical point. To understand the origin of this anomalous behavior, we have characterized the magnetic ordering and crystalline electric field (CEF) scheme of this system. While magnetic Bragg peaks are not resolved in neutron powder diffraction, coherent oscillations are observed in zero-field $\ensuremath{\mu}\mathrm{SR}$ below ${T}_{\mathrm{C}}$, which are consistent with in-plane ferromagnetic ordering consisting of reduced Ce moments. From analyzing the magnetic susceptibility and inelastic neutron scattering, we propose a CEF-level scheme which accounts for the easy-plane magnetocrystalline anisotropy, where the low lying first excited CEF exhibits significantly stronger hybridization than the ground state. These results suggest that the orbital anisotropy of the ground state and low-lying excited state doublets are important for realizing anisotropic electronic coupling between the $f$ and conduction electrons, which gives rise to the highly anisotropic hybridization observed in photoemission experiments.

Preparing materials which simultaneously exhibit spontaneous magnetic and electrical polarisations is challenging as the electronic features which are typically used to stabilise each of these two polarisations in materials are contradictory. Here we show that by performing low-temperature cation-exchange reactions on a hybrid improper ferroelectric material, Li2SrTa2O7, which adopts a polar structure due to a cooperative tilting of its constituent TaO6 octahedra rather than an electronically driven atom displacement, a paramagnetic polar phase, MnSrTa2O7, can be prepared. On cooling below 43 K the Mn2+ centres in MnSrTa2O7 adopt a canted antiferromagnetic state, with a small spontaneous magnetic moment. On further cooling to 38 K there is a further transition in which the size of the ferromagnetic moment increases coincident with a decrease in magnitude of the polar distortion, consistent with a coupling between the two polarisations., Fabricating materials with simultaneously spontaneous magnetic and electrical polarisations is challenging due to contradictory electronic features. Here, the authors report a synthesis path toward a perovskite MnSrTa2O7 by performing low-temperature cation-exchange reactions on Li2SrTa2O7.

The linear magnetoelectric effect and multiferroicity phenomena occur independently due to breaking inversion symmetry below the magnetically ordered state of either transition metal or rare-earth ions. Here, we report the occurrence of a linear magnetoelectric effect and magnetic field-induced ferromagnetism and ferroelectricity below ${T}_{\mathrm{N}}^{R}$ in the orthorhombic green phases ${R}_{2}\mathrm{BaCu}{\mathrm{O}}_{5}$ ($R=\mathrm{Dy}$ and Ho). They undergo a long-range antiferromagnetic ordering of ${\mathrm{Cu}}^{2+}$ (${T}_{\mathrm{N}}^{\mathrm{Cu}}=18.5$ and 17.5 K) and ${R}^{3+}$ ions (${T}_{\mathrm{N}}^{\mathrm{Dy}}=10.7\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ and ${T}_{\mathrm{N}}^{\mathrm{Ho}}=8\phantom{\rule{0.16em}{0ex}}\mathrm{K}$). The neutron diffraction study reveals that these compounds undergo a first-order magnetic transition from the high-temperature centrosymmetric antiferromagnetic phase (${P}_{\mathrm{b}}{112}_{1}/n$) to the low-temperature noncentrosymmetric phases $Pn{m}^{\ensuremath{'}}a$ (Dy) and $P{112}_{1}^{\ensuremath{'}}/a$ (Ho), which allow linear magnetoelectric coupling. This is consistent with field-induced electric polarization, below ${T}_{\mathrm{N}}^{R}$, which varies linearly up to \ensuremath{\sim}1.2 T. Above a critical field $({H}_{\mathrm{c}}g1.2\phantom{\rule{0.16em}{0ex}}\mathrm{T})$, both compounds exhibit metamagnetic transitions with magnetization close to the saturation value ${M}_{s} \ensuremath{\sim}10.1\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{\mathrm{B}}/\mathrm{f}.\mathrm{u}.$ (Dy) and $\ensuremath{\sim}11.8\phantom{\rule{0.16em}{0ex}}{\ensuremath{\mu}}_{\mathrm{B}}/\mathrm{f}.\mathrm{u}.$ (Ho) at 7 T. Above the metamagnetic transition, a new polar state appears with large electric polarization, indicating field-induced ferroelectricity. We discuss the important role of $4f\text{\ensuremath{-}}3d$ coupling in determining the ground state magnetic structure responsible for the magnetoelectric coupling in both compounds.

The hidden order phase in $\mathrm{U}{\mathrm{Ru}}_{2}{\mathrm{Si}}_{2}$ is highly sensitive to electronic doping. A special interest in silicon-to-phosphorus substitution is due to the fact that it may allow one, in part, to isolate the effects of tuning the chemical potential from the complexity of the correlated $f$ and $d$ electronic states. We investigate the new antiferromagnetic phase that is induced in $\mathrm{U}{\mathrm{Ru}}_{2}{\mathrm{Si}}_{2\ensuremath{-}x}{\mathrm{P}}_{x}$ at $x\ensuremath{\gtrsim}0.27$. Time-of-flight neutron diffraction of a single crystal ($x=0.28$) reveals $c$-axis collinear ${\mathbf{q}}_{\mathrm{m}}=(\frac{1}{2},\frac{1}{2},\frac{1}{2})$ magnetic order with localized magnetic moments ($\ensuremath{\sim}2.1$--$2.6\phantom{\rule{0.28em}{0ex}}{\ensuremath{\mu}}_{\mathrm{B}}$). This points to an unexpected analogy between the (Si,P) and (Ru,Rh) substitution series. Through further comparisons with other tuning studies of ${\mathrm{URu}}_{2}{\mathrm{Si}}_{2}$, we are able to delineate the mechanisms by which silicon-to-phosphorus substitution affects the system. In particular, both the localization of itinerant $5f$ electrons as well as the choice of ${\mathbf{q}}_{m}$ appear to be consequences of the increase in chemical potential. Further, enhanced exchange interactions are induced by chemical pressure and lead to magnetic order, in which an increase in interlayer spacing may play a special role.

The quantum magnet KOsO4 has been characterized by a combination of X-ray and neutron diffraction techniques. The tetrahedrally coordinated Os7+ 5d1S = 1/2 cations were determined to order antiferromagnetically along the c axis below 35 K. A miniscule ordered magnetic moment of 0.46(18) μB was determined per Os7+ cation.

We investigate the temperature evolution of the magnetic structure of ${\mathrm{V}}_{1/3}{\mathrm{NbS}}_{2}$ using neutron diffraction techniques. We find that ${\mathrm{V}}_{1/3}{\mathrm{NbS}}_{2}$ has two propagation vectors: ${\mathbf{k}}_{\mathbf{0}}=(0,0,0)$ and ${\mathbf{k}}_{\mathbf{1}}=(0,0,\frac{1}{3})$. The ${\mathbf{k}}_{\mathbf{0}}$ vector can be associated with an antiferromagnetic ordering of in-plane moments with a refined value of $0.90(5){\ensuremath{\mu}}_{\mathrm{B}}$, and ${\mathbf{k}}_{\mathbf{1}}$ can be associated with moments along the $c$ axis in an up-down-down configuration with refined values of $1.21(12){\ensuremath{\mu}}_{\mathrm{B}}$ and $0.61(6){\ensuremath{\mu}}_{\mathrm{B}}$. Both ${\mathbf{k}}_{\mathbf{0}}$ and ${\mathbf{k}}_{\mathbf{1}}$ magnetic components couple with an out-of-plane ferromagnetic moment consistent with magnetization data. Furthermore, single-crystal neutron diffraction shows evidence of diffuse magnetic scattering between the (010) and ($01\ifmmode\pm\else\textpm\fi{}\frac{1}{3}$) Bragg peaks. We also characterize the field and temperature evolution of the magnetic structure in ${\mathrm{V}}_{1/3}{\mathrm{NbS}}_{2}$ by magnetic susceptibility and heat capacity measurements. The dc susceptibility measurements give an antiferromagnetic transition temperature of ${T}_{\mathrm{N}}=50$ K, and the field scans reveal that the moment does not saturate at magnetic fields up to 100 kOe.

The low-temperature structure of ${\mathrm{Bi}}_{0.68}{\mathrm{Ca}}_{0.32}{\mathrm{MnO}}_{3}$ has been solved from electron and neutron diffraction data. The quantitative simultaneous refinement indicates an ordering of the Mn cations in a ``stripe/chess''-like pattern. The ordering is accompanied by the formation of short Mn---Mn distances and the rearrangement of the Mn---O bonds indicating the development of complex extended ``orbital molecules.'' The primary order parameter breaks inversion symmetry and allows the generation of a spontaneous electrical polarization as the secondary order parameter. The neutron data at low temperature indicate the coexistence of a pseudo-CE long-range-ordered structure with a strongly reduced moment and short-range ferromagnetic correlations. These results indicate an intricate competition between the charge, orbital, and magnetic degrees of freedom and the ${\mathrm{Bi}}^{3+}$ stereoactivity in this manganite system.

Understanding structural responses of metal-organic frameworks (MOFs) to external stimuli such as the inclusion of guest molecules and temperature/pressure has gained increasing attention in many applications, for example, manipulation and manifesto smart materials for gas storage, energy storage, controlled drug delivery, tunable mechanical properties, and molecular sensing, to name but a few. Herein, neutron and synchrotron diffractions along with Rietveld refinement and density functional theory calculations have been used to elucidate the responsive adsorption behaviors of defect-rich Zr-based MOFs upon the progressive incorporation of ammonia (NH