Water Encapsulated [(FeSe)Se] Clusters in [Na(HO)][FeSe].

[Na(HO)][FeSe] was synthesized using hydrothermal methods and characterized by single-crystal X-ray diffraction, Fe Mössbauer spectroscopy, magnetization, and muon spin resonance (μSR) measurements. The cubic crystal structure (space group 23, = 11.785 Å, = 2) contains heterocubane-type clusters with symmetry.

Extended Berry Curvature Tail in Ferromagnetic Weyl Semimetals NiMnSb and PtMnSb.

Heusler compounds belong to a large family of materials and exhibit numerous physical phenomena with promising applications, particularly ferromagnetic Weyl semimetals for their use in spintronics and memory devices. Here, anomalous Hall transport is reported in the room-temperature ferromagnets NiMnSb (half-metal with a Curie temperature (T) of 660 K) and PtMnSb (pseudo half-metal with a T of 560 K). They exhibit 4 µ/f.

A Trinuclear High-Spin Iron(III) Complex with a Geometrically Frustrated Spin Ground State Featuring Negligible Magnetic Anisotropy and Antisymmetric Exchange.

The trinuclear high-spin iron(III) complex [FeCl(saltag)(py)]ClO {Hsaltag = 1,2,3-tris[(5-bromo-salicylidene)amino]guanidine} was synthesized and characterized by several experimental and theoretical methods. The iron(III) complex exhibits molecular 3-fold symmetry imposed by the rigid ligand backbone and crystallizes in trigonal space group 3̅ with the complex cation lying on a crystallographic axis. The high-spin states ( = /) of the individual iron(III) ions were determined by Mößbauer spectroscopy and confirmed by CASSCF/CASPT2 ab initio calculations.

Static and Resonant Properties and Magnetic Phase Diagram of LiMnTeO.

Physical properties of the mixed-valent tellurate of lithium and manganese, LiMn2TeO6, were investigated in measurements of ac and dc magnetic susceptibility χ, magnetization M, specific heat Cp, electron spin resonance (ESR), and nuclear magnetic resonance (NMR) in the temperature range 2−300 K under magnetic field up to 9 T. The title compound orders magnetically in two steps at T1 = 20 K and T2 = 13 K. The intermediate phase at T2 < T < T1 is fully suppressed by magnetic field µ0H of about 4 T.

Unconventional Spin State Driven Spontaneous Magnetization in a Praseodymium Iron Antimonide.

Consolidating a microscopic understanding of magnetic properties is crucial for a rational design of magnetic materials with tailored characteristics. The interplay of 3d and 4f magnetism in rare-earth transition metal antimonides is an ideal platform to search for such complex behavior. Here the synthesis, crystal growth, structure, and complex magnetic properties are reported of the new compound Pr Fe Sb as studied by magnetization and electrical transport measurements in static and pulsed magnetic fields up to 56 T, powder neutron diffraction, and Mößbauer spectroscopy.

Mechanistic Studies on the Hexadecafluorophthalocyanine-Iron-Catalyzed Wacker-Type Oxidation of Olefins to Ketones*.

The hexadecafluorophthalocyanine-iron complex FePcF was recently shown to convert olefins into ketones in the presence of stoichiometric amounts of triethylsilane in ethanol at room temperature under an oxygen atmosphere. Herein, we describe an extensive mechanistic investigation for the conversion of 2-vinylnaphthalene into 2-acetylnaphthalene as model reaction. A variety of studies including deuterium- and O -labeling experiments, ESI-MS, and Fe Mössbauer spectroscopy were performed to identify the intermediates involved in the catalytic cycle of the oxidation process.

Unsplit superconducting and time reversal symmetry breaking transitions in SrRuO under hydrostatic pressure and disorder.

There is considerable evidence that the superconducting state of SrRuO breaks time reversal symmetry. In the experiments showing time reversal symmetry breaking, its onset temperature, T, is generally found to match the critical temperature, T, within resolution. In combination with evidence for even parity, this result has led to consideration of a d ± id order parameter.

Piezoelectric-driven uniaxial pressure cell for muon spin relaxation and neutron scattering experiments.

We present a piezoelectric-driven uniaxial pressure cell that is optimized for muon spin relaxation and neutron scattering experiments and that is operable over a wide temperature range including cryogenic temperatures. To accommodate the large samples required for these measurement techniques, the cell is designed to generate forces up to ∼1000 N. To minimize the background signal, the space around the sample is kept as open as possible.

A semiconducting layered metal-organic framework magnet.

The realization of ferromagnetism in semiconductors is an attractive avenue for the development of spintronic applications. Here, we report a semiconducting layered metal-organic framework (MOF), namely KFe[(2,3,9,10,16,17,23,24-octahydroxy phthalocyaninato)Fe] (KFe[PcFe-O]) with spontaneous magnetization. This layered MOF features in-plane full π-d conjugation and exhibits semiconducting behavior with a room temperature carrier mobility of 15 ± 2 cm V s as determined by time-resolved Terahertz spectroscopy.

Coexistence of 3d-ferromagnetism and superconductivity in [(Li1-x Fex )OH](Fe1-y Liy )Se.

Superconducting [(Li1-x Fex )OH](Fe1-y Liy )Se (x≈0.2, y≈0.08) was synthesized by hydrothermal methods and characterized by single-crystal and powder X-ray diffraction.

Microscopic coexistence of superconductivity and magnetism in Ba(1-x)K(x)Fe2As2.

It is widely believed that, in contrast to its electron-doped counterparts, the hole-doped compound Ba(1-x)K(x)Fe(2)As(2) exhibits a mesoscopic phase separation of magnetism and superconductivity in the underdoped region of the phase diagram. Here, we report a combined high-resolution x-ray powder diffraction and volume-sensitive muon spin rotation study of Ba(1-x)K(x)Fe(2)As(2) showing that this paradigm does not hold true in the underdoped region of the phase diagram (0≤x≤0.25).

Crystal structure and magnetic properties of FeTe2O5X (X=Cl, Br): a frustrated spin cluster compound with a new Te(IV) coordination polyhedron.

A new layered transition metal oxohalide, FeTe2O5ClxBr1-x, has been identified. It crystallizes in the monoclinic space group P21/c. The unit cell for FeTe2O5Br is a = 13.

Structural variety and magnetic properties of tetranuclear nickel(II) complexes with a central mu4-azide.

Using a set of pyrazolate-based dinucleating ligands with thioether sidearms and a set of different carboxylates, seven tetranuclear nickel(II) complexes of types [L2Ni4(N3)3(O2CR)2](ClO4) (1) and [L2Ni4(N3)(O2CR)4](ClO4) (2) featuring an unprecedented central mu4-1,1,3,3-azide could be isolated and fully characterized. X-ray crystal structures are discussed for 1a,b,e and 2b. The mu4-1,1,3,3-azide is symmetric in all cases except 1a but exhibits distinct binding modes with significantly different Ni-N(azide)-Ni angles and Ni-NNN-Ni torsions in type 1 and 2 complexes, which indicates high structural flexibility of this novel bridging unit.