Advances in high-pressure laser floating zone growth: The Laser Optical Kristallmacher II (LOKII).

The optical floating zone crystal growth technique is a well-established method for obtaining large, high-purity single crystals. While the floating zone method has been constantly evolving for over six decades, the development of high-pressure (up to 1000 bar) growth systems has only recently been realized via the combination of laser-based heating sources with an all-metal chamber. While our inaugural high-pressure laser floating zone furnace design demonstrated the successful growth of new volatile and metastable phases, the furnace design faces several limitations with imaging quality, heating profile control, and chamber cooling power.

Hybrid Iodide Perovskites of Divalent Alkaline Earth and Lanthanide Elements.

Hybrid halide perovskites AMX (A = ammonium cation, M = divalent cation, X = Cl, Br, I) have been extensively studied but have only previously been reported for the divalent carbon group elements Ge, Sn, and Pb. While they have displayed an impressive range of optoelectronic properties, the instability of Ge and Sn and the toxicity of Pb have stimulated significant interest in finding alternatives to these carbon group-based perovskites. Here, we describe the low-temperature solid-state synthesis of five new hybrid iodide perovskites centered around divalent alkaline earth and lanthanide elements, with the general formula AMI (A = methylammonium, MA; M = Sr, Sm, Eu, and A = formamidinium, FA; M = Sr, Eu).

Elusive Double Perovskite Iodides: Structural, Optical, and Magnetic Properties.

Halide double perovskites [A M M X ] are an important class of materials that have garnered substantial interest as non-toxic alternatives to conventional lead iodide perovskites for optoelectronic applications. While numerous studies have examined chloride and bromide double perovskites, reports of iodide double perovskites are rare, and their definitive structural characterization has not been reported. Predictive models have aided us here in the synthesis and characterization of five iodide double perovskites of general formula Cs NaLnI (Ln=Ce, Nd, Gd, Tb, Dy).

Metal-Metal-Bonded Fe Clusters with Slow Magnetic Relaxation.

Reaction of FeBr with Li(N═CBu) (0.5 equiv) and Zn (2 equiv) results in the formation of the formally mixed-valent cluster [FeBr(N═CBu)] () in moderate yield. The subsequent reaction of with Na(N═CBu) results in formation of [FeBr(N═CBu)] (), also in moderate yield.

Hybrid Layered Double Perovskite Halides of Transition Metals.

Hybrid layered double perovskite (HLDP) halides comprise hexacoordinated 1+ and 3+ metals in the octahedral sites within a perovskite layer and organic amine cations between the layers. Progress on such materials has hitherto been limited to compounds containing main group 3+ ions isoelectronic with Pb (such as Sb and Bi). Here, we report eight HLDP halides from the family, where = -phenylenediammonium (PPDA), 1,4-butanediammonium (1,4-BDA), or 1,3-propanediammonium (1,3-PDA); = Cu or Ag; = Ru or Mo; X = Cl or Br.

Metal-Metal Bonding as an Electrode Design Principle in the Low-Strain Cluster Compound LiScMoO.

Electrode materials for Li-ion batteries require optimization along several disparate axes related to cost, performance, and sustainability. One of the important performance axes is the ability to retain structural integrity though cycles of charge/discharge. Metal-metal bonding is a distinct feature of some refractory metal oxides that has been largely underutilized in electrochemical energy storage, but that could potentially impact structural integrity.

Unconventional chiral charge order in kagome superconductor KVSb.

Intertwining quantum order and non-trivial topology is at the frontier of condensed matter physics. A charge-density-wave-like order with orbital currents has been proposed for achieving the quantum anomalous Hall effect in topological materials and for the hidden phase in cuprate high-temperature superconductors. However, the experimental realization of such an order is challenging.

Chemical Control of Spin-Orbit Coupling and Charge Transfer in Vacancy-Ordered Ruthenium(IV) Halide Perovskites.

Vacancy-ordered double perovskites are attracting significant attention due to their chemical diversity and interesting optoelectronic properties. With a view to understanding both the optical and magnetic properties of these compounds, two series of Ru halides are presented; A RuCl and A RuBr , where A is K, NH , Rb or Cs. We show that the optical properties and spin-orbit coupling (SOC) behavior can be tuned through changing the A cation and the halide.

Are AuPd ( = Sc, Y and = Al, Ga, In), Heusler Compounds Superconductors without Inversion Symmetry?

Heusler compounds with 2:1:1 stoichiometry either have a centrosymmetric Cu 2 MnAl structure or an Li 2 AgSb structure without a centre of inversion. The centrosymmetry is always lost in quaternary Heusler compounds with 1:1:1:1 stoichiometry and LiMgPdSn structure. This presents the possibility of realizing non-centrosymmetric superconductors in the family of Heusler compounds.