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Exceptionally electron‐rich, nearly trigonal‐planar tricyanidometalate anions [Fe(CN)3]7− and [Ru(CN)3]7− were stabilized in LiSr3[Fe(CN)3] and AE3.5[M(CN)3] (AE=Sr, Ba; M=Fe, Ru). They are the first examples of group 8 elements with the oxidation state of −IV. Microcrystalline powders were obtained by a solid‐state route, single crystals from alkali metal flux. While LiSr3[Fe(CN)3] crystallizes in P63/m, the polar space group P63 with three‐fold cell volume for AE3.5[M(CN)3] is confirmed by second harmonic generation. X‐ray diffraction, IR and Raman spectroscopy reveal longer C−N distances (124–128 pm) and much lower stretching frequencies (1484–1634 cm−1) than in classical cyanidometalates. Weak C−N bonds in combination with strong M−C π‐bonding is a scheme also known for carbonylmetalates. Instead of the formal notation [Fe−IV(CN−)3]7−, quantum chemical calculations reveal non‐innocent intermediate‐valent CN1.67− ligands and a closed‐shell d10 configuration for Fe, that is, Fe2−., The electron‐rich cyanidometalates [Fe(CN)3]7− and [Ru(CN)3]7− represent the first examples of group 8 elements with an oxidation state of −IV. DFT calculations reveal a nominal d10s0 configuration, which corresponds to an effective charge of 2−. The high negative charge also weakens the C−N bonds by the population of antibonding states.

Five substituted oxohydroxoferrates K2–x(Fe,M)4O7–y(OH)y (M=Si, Ge, Ti, Mn, Ir) were synthesized in a potassium hydroxide hydroflux with a molar base‐water ratio q(K) of about 0.9. While the hexagonal prisms of K2–x(Fe,Ti)4O7–y(OH)y crystallize in P63/mcm, all other compounds form hexagonal plates with the trigonal space group Purn:x-wiley:14341948:media:ejic202000891:ejic202000891-math-0001 1 m. The crystal structure of the oxohydroxoferrates resembles ß‐alumina. It consists of honeycomb layers urn:x-wiley:14341948:media:ejic202000891:ejic202000891-math-0002 Fe2O6] of edge‐sharing [FeO6] octahedra, where the hexagonal voids are capped by vertex‐sharing [FeO4] tetrahedra pairs. The cavities between the oxoferrate layers host the potassium ions. Depending on M, the substitution affects different iron positions and varies between 5 and 20 %. The magnetic structures of the antiferromagnetic compounds were determined by neutron powder diffraction. The potassium ion conductivity was characterized by electrochemical impedance spectroscopy at room temperature. By storing the oxohydroxoferrates in air or annealing them at 700 °C the ion conductivity was significantly increased, e. g. to 5.0 ⋅ 10−3 S cm−1 for a pressed pellet of the iridium substituted compound.

Fine-tuning chemistry by doping with transition metals enables new perspectives for exploring Kitaev physics on a two-dimensional (2D) honeycomb lattice of α-RuCl3, which is promising in the field of quantum information protection and quantum computation. The key parameters to vary by doping are both Heisenberg and Kitaev components of the nearest-neighbor exchange interaction between the Jeff = 1/2 Ru3+ spins, depending strongly on the peculiarities of the crystal structure. Here, we present crystal growth by chemical vapor transport and structure elucidation of a solid solution series Ru1- xCr xCl3 (0 ≤ x ≤ 1), with Cr3+ ions coupled to the Ru3+ Kitaev host. The Cr3+ substitution preserves the honeycomb type lattice of α-RuCl3 and creates mixed occupancy of Ru/Cr sites without cationic order within the layers as confirmed by single-crystal X-ray diffraction and transmission electron microscopy investigations. In contrast to high-quality single crystals of α-RuCl3 with ABAB-stacked layers, the ternary compounds demonstrate a significant stacking disorder along the c-axis direction as evidenced by X-ray diffraction and high resolution scanning transmission electron microscopy (HR-STEM). Raman spectra of substituted samples are in line with the symmetry conservation of the parent lattice upon chromium doping. At the same time, our magnetic susceptibility data indicate that the Kitaev physics of α-RuCl3 is increasingly suppressed by the dominant spin-only driven magnetism of Cr3+ ( S = 3/2) in Ru1- xCr xCl3.

A new calcium iron ruthenium hydrogarnet with the approximate composition Ca3(Ru2− x Fe x )(FeO4)2− y (H4O4)1+ y (x=1, y≈0.35) has been obtained by hydrothermal synthesis under oxidizing alkaline conditions. The compound crystallizes in the cubic space group Ia3̅d (No. 230) with a lattice parameter of a=12.4804(4) Å (T=100 K) and Z=8. The octahedral site of the garnet structure is equally occupied by Ru and Fe, whereas the tetrahedral site is partially occupied by Fe only. A partial substitution of the oxide anions by hydroxide ions is necessary for charge balancing, corresponding to the so-called hydrogarnet defects. The presence of hydroxide groups is proven by infrared spectroscopy. 57Fe Mössbauer spectroscopic data provide evidence for two different Fe3+ coordination environments as well as a magnetic ordering of two iron substructures with the respective ordering temperature above room temperature. The crystal composition was verified by energy-dispersive X-ray spectroscopy and the thermal behavior of the calcium iron ruthenate was studied by difference thermal analysis.

Fine-tuning chemistry by doping with transition metals enables new perspectives for exploring Kitaev physics on a two-dimensional (2D) honeycomb lattice of α-RuCl

Initiated by the effective dibromination of syn-BN-heteroacenes, a series of BN-containing conjugated oligomers was successfully synthesized upon transition-metal-catalyzed cross coupling. Their electronic structures can be finely tailored through varying the fused backbone or terminal substituents, endowing them with tunable luminescent properties within blue-violet regions.

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The reaction of Fe(NO3)3∙9 H2O with KOH under hydroflux conditions at about 200 °C produces red crystals of K2−xFe4O7–x(OH)x in a quantitative yield. In the crystal structure, edge-sharing [FeO6] octahedra form 2D-[Fe2O6] honeycomb nets. Pillars consisting of pairs of vertex-sharing [FeO4] tetrahedra link the honeycomb layers and form columnar halls in which the potassium ions are located. The trigonal (P3̅1m) and the hexagonal (P63/mcm) polytypes of K2−xFe4O7–x(OH)x show oriented intergrowth. The sub-stoichiometric potassium content (x = 0.3) is compensated by hydroxide ions. K2−xFe4O7–x(OH)x is an antiferromagnet above 2 K and its magnetic structure was determined by neutron powder diffraction. Under ambient conditions K2−xFe4O7–x(OH)x hydrolyzes and K2CO3·H2O forms gradually on the surface of the K2−xFe4O7–x(OH)x crystals. Upon annealing at air at about 500 °C, the potassium atoms in the columnar halls start to order into a superstructure.

The reaction of Fe(NO3)3∙9 H2O with KOH under hydrofluxconditions at about 200 °C produces red crystals of K2−xFe4O7 in a quantitative yield. In the crystal structure, edge-sharing [FeO6]octahedra form [ ∞Fe2O6] honeycomb nets. Pillars consisting of pairs of vertex-sharing [FeO4] tetrahedra link the honeycomb layers and form columnar halls in which the potassium ions are located. The trigonal (P3 1m) and the hexagonal (P63/mcm) polytypes of K2−xFe4O7 show oriented intergrowth. The sub-stoichiometric potassium content (x ≈ 0.3) is compensated by iron(IV), as supported by 57Fe Mößbauer spectroscopy, besides the dominating iron(III). K2−xFe4O7 is an antiferromagnet above 2 K and its magnetic structure was determined by neutron powder diffraction. Under ambient conditions, K2CO3·H2O forms gradually on the surface of K2−xFe4O7 crystals. Upon annealing at air at about 500 °C, the potassium atoms in the columnar halls start to order into a superstructure. The thermal decomposition of K2−xFe4O7 proceeds via a topotactic transformation into K1+x’Fe11O17, adopting the rhombohedral β’’ or the hexagonal β-aluminate-type structure, before γ-Fe2O3 is formed above 950 °C, which then converts into thermodynamically stable α-Fe2O3.

The reaction of Fe(NO3)3⋅9 H2O with KOH under hydroflux conditions at about 200 °C produces red crystals of K2−xFe4O7−x(OH)x in a quantitative yield. In the crystal structure, edge‐sharing [FeO6] octahedra form ∞2[ Fe2O6] honeycomb nets. Pillars consisting of pairs of vertex‐sharing [FeO4] tetrahedra link the honeycomb layers and form columnar halls in which the potassium ions are located. The trigonal (P 3‾ 1m) and the hexagonal (P63/mcm) polytypes of K2−xFe4O7−x(OH)x show oriented intergrowth. The sub‐stoichiometric potassium content (x≈0.3) is compensated by hydroxide ions. K2−xFe4O7−x(OH)x is an antiferromagnet above 2 K and its magnetic structure was determined by neutron powder diffraction. Under ambient conditions, K2−xFe4O7−x(OH)x hydrolyzes and K2CO3 ⋅ H2O forms gradually on the surface of the K2−xFe4O7−x(OH)x crystals. Upon annealing at air at about 500 °C, the potassium atoms in the columnar halls start to order into a superstructure. The thermal decomposition of K2−xFe4O7−x(OH)x proceeds via a topotactic transformation into K1+x′Fe11O17, adopting the rhombohedral β’’ or the hexagonal β‐aluminate‐type structure, before γ‐Fe2O3 is formed above 950 °C, which then converts into thermodynamically stable α‐Fe2O3.

A convenient approach for a controlled and high-yield synthesis of copper-deficient Cu3−xP (0.1 < x < 0.7) is reported that makes use of ionic liquids with highly nucleophilic “naked” halide anions. Halide anions drastically enhance the reactivity of the white phosphorus precursor and kinetically disfavour the formation of phosphorus-rich side products. Cu3−xP shows a high degree of tolerance for cation vacancies without mayor structural reorganisation, as evidenced by X-ray diffraction and solid-state nuclear magnetic resonance spectroscopy. Measurements of the electric 29 properties reveal that Cu3−xP is a bad metallic p-type conductor. The resistivity is composition-dependent and displays a distinct anomaly from a phase transition, leading to the discovery and structural characterisation of two hitherto unknown low temperature polymorphs. Electrochemical evaluation of copper-deficient Cu3−xP as anode material for lithium ion batteries reveals a drastic change in the cycling mechanism leading to an increase of the initial capacities by about 70 %. This work gives a comprehensive insight into the chemical and structural features of copper-deficient Cu3−xP and should lead to an improved understanding of its properties, not only for battery applications.

$\alpha$-RuCl$_3$ has attracted enormous attention since it has been proposed as a prime candidate to study fractionalized magnetic excitations akin to Kitaev's honeycomb-lattice spin liquid. We have performed a detailed specific-heat investigation at temperatures down to $0.4$ K in applied magnetic fields up to $9$ T for fields parallel to the $ab$ plane. We find a suppression of the zero-field antiferromagnetic order, together with an increase of the low-temperature specific heat, with increasing field up to $\mu_0H_c\approx 6.9$ T. Above $H_c$, the magnetic contribution to the low-temperature specific heat is strongly suppressed, implying the opening of a spin-excitation gap. Our data point toward a field-induced quantum critical point (QCP) at $H_c$; this is supported by universal scaling behavior near $H_c$. Remarkably, the data also reveal the existence of a small characteristic energy scale well below $1$~meV above which the excitation spectrum changes qualitatively. We relate the data to theoretical calculations based on a $J_1$--$K_1$--$\Gamma_1$--$J_3$ honeycomb model., Comment: 5 pages, 4 figures (main text), plus Supplemental Material

Five new coordination polymers, [ Mn ( DPA ) ( Me 4 bpz ) ( H 2 O ) ] ( I ) ∞ 1 , [ Cu ( DPA ) ( Me 4 bpz ) 2 ] · H 2 O ( II ) ∞ 1 , [ Ag 4 ( OAc ) 2 ( Me 4 bpz ) 3 ( H 2 O ) 1.56 ] ( III ) ∞ 2 , [ Zn ( DPA ) ( Me 4 bpz ) ] · 0.61 H 2 O ( IV ) ∞ 3 and [ Cd ( DPA ) ( Me 4 bpz ) ] ( V ) ∞ 3 [DPA: diphenic acid dianion, OAc: acetate, Me4bpz: 3,3′,5,5′-tetramethyl-4,4′-bipyrazole], were obtained from acetate hydrates of Mn2+, Cu2+, Ag+, Zn2+ and Cd2+ and a mixed ligand system consisting of Me4bpz and diphenic acid by hydrothermal synthesis under similar conditions. Their crystal structures were determined by means of X-ray single crystal structure analysis. Furthermore, the compounds were characterized by means of elemental analysis and IR spectroscopy. The polymers I and II exhibit one-dimensional chain structures with only one type of bridging ligand, whereas the polymers IV and V realize three-dimensional coordination frameworks with diamond topology involving both ligand types as bridging ligands. Compound III contains a two-dimensional cationic framework which is charge compensated by acetate anions. The coordination environments of the metal centers are predominant directly supported by N–H ⋯ O hydrogen bonds providing further evidence for the bipyrazole-carboxylate supramolecular synthon.

Application of high-pressure high-temperature conditions (3.5 GPa at 1673 K for 5 h) to mixtures of the elements (RE:B:S=1:3:6) yielded crystalline samples of the isotypic rare earth-thioborate-sulfides RE{sub 9}[BS{sub 3}]{sub 2}[BS{sub 4}]{sub 3}S{sub 3}, (RE=Dy-Lu), which crystallize in space group P6{sub 3} (Z=2/3) and adopt the Ce{sub 6}Al{sub 3.33}S{sub 14} structure type. The crystal structures were refined from X-ray powder diffraction data by applying the Rietveld method. Dy: a=9.4044(2) A, c=5.8855(3) A; Ho: a=9.3703(1) A, c=5.8826(1) A; Er: a=9.3279(12) A, c=5.8793(8) A; Tm: a=9.2869(3) A, c=5.8781(3) A; Yb: a=9.2514(5) A, c=5.8805(6) A; Lu: a=9.2162(3) A, c=5.8911(3) A. The crystal structure is characterized by the presence of two isolated complex ions [BS{sub 3}]{sup 3-} and [BS{sub 4}]{sup 5-} as well as [{open_square}(S{sup 2-}){sub 3}] units. -- Graphical abstract: Isotypic rare earth-thioborate-sulfides RE{sub 9}[BS{sub 3}]{sub 2}[BS{sub 4}]{sub 3}S{sub 3}, (RE=Dy-Lu) were prepared by application of high-pressure high-temperature conditions to mixtures of the elements. Their crystal structures are characterized by presence of the two isolated complex ions [BS{sub 3}]{sup 3-} and [BS{sub 4}]{sup 5-} as well as [{open_square}(S{sup 2-}){sub 3}] units. Quantum mechanical calculations revealed the arrangement of the intrinsic vacancies. Display Omitted Research Highlights: {yields} Application of high-pressure high-temperature conditions to mixturesmore » of the elements yields crystalline samples of the isotypic rare earth-thioborate-sulfides RE{sub 9}[BS{sub 3}]{sub 2}[BS{sub 4}]{sub 3}S{sub 3}, (RE=Dy-Lu). {yields} RE{sub 9}[BS{sub 3}]{sub 2}[BS{sub 4}]{sub 3}S{sub 3}, (RE=Dy-Lu) crystallize in space group P6{sub 3} (Z=2/3) and adopt the Ce{sub 6}Al{sub 3.33}S{sub 14} structure type. {yields} The crystal structure of RE{sub 9}[BS{sub 3}]{sub 2}[BS{sub 4}]{sub 3}S{sub 3}, (RE=Dy-Lu) is characterized by the presence of two isolated complex ions [BS{sub 3}]{sup 3-} and [BS{sub 4}]{sup 5-} as well as [{open_square}(S{sup 2-}){sub 3}] units. {yields} The vacancies in Lu{sub 9}[BS{sub 3}]{sub 2}[BS{sub 4}]{sub 3}S{sub 3} are located at the trigonal planar coordinated boron site with preferred ordering -B2-B2-{open_square}-B2-B2-{open_square}- along [001].« less

The orthothioborates Ce[BS{sub 3}], Pr[BS{sub 3}] and Nd[BS{sub 3}] were prepared from mixtures of the rare earth (RE) metals together with amorphous boron and sulfur summing up to the compositions CeB{sub 3}S{sub 6}, PrB{sub 5}S{sub 9} and NdB{sub 3}S{sub 6}. The following preparation routes were used: solid state reactions with maximum temperatures of 1323 K and high-pressure high-temperature syntheses at 1173 K and 3 GPa. Pr[BS{sub 3}] and Nd[BS{sub 3}] were also obtained from rare earth chlorides RECl{sub 3} and sodium thioborate Na{sub 2}B{sub 2}S{sub 5} by metathesis type reactions at maximum temperatures of 1073 K. The crystal structure of the title compounds was determined from X-ray powder diffraction data. The thioborates are isotypic and crystallize in the orthorhombic spacegroup Pna2{sub 1} (No. 33; Z=4; Ce: a=7.60738(6)A, b=6.01720(4)A, c=8.93016(6)A; Pr: a=7.56223(4)A, b=6.00876(2)A, c=8.89747(4)A; Nd: a=7.49180(3)A, b=6.00823(2)A, c=8.86197(3)A) . The crystal structures contain isolated [BS{sub 3}]{sup 3-} groups with boron in trigonal-planar coordination. The sulfur atoms form the vertices of undulated kagome nets, which are stacked along [100] according to the sequence ABAB. Within these nets every second triangle is occupied by boron and the large hexagons are centered by rare earth ions, which are surrounded by overall nine sulfur species.more » - Abstract: Graphical Abstract Legend (TOC Figure): Table of Contents Figure The isotypic orthothioborates Ce[BS{sub 3}], Pr[BS{sub 3}] and Nd[BS{sub 3}] were prepared using different preparation routes. The crystal structure of the title compounds was determined from X-ray powder diffraction data. The crystal structures contain isolated [BS{sub 3}]{sup 3-} groups with boron in trigonal-planar coordination. The sulfur atoms form the vertices of corrugated kagome nets (sketched with blue dotted lines), which are stacked along [100] according to the sequence ABAB. Within these nets every second triangle is occupied by boron and the large hexagons are centered by rare earth ions, which are surrounded by overall nine sulfur species.« less

Nine new coordination polymers, namely 2∞[Ag(Hp2CA)(Me4bpz)] (I), 3∞[Zn2(p2CA)2(Me4bpz)] (II), 2∞[Cd(OAc)2(Me4bpz)(H2O)] (III), 1∞[Ag2(m2CA)(Me4bpz)2] (IV), 3∞[Zn(m2CA)(Me4bpz)] (V), 2∞[Cd(m2CA)(Me...

Stable 3-oxosultams were synthesized by oxidation of the 2-hetaryl-substituted isothiazolium salts. X-Ray crystal structure analyses of the sultams reveal the existence of strong and weak hydrogen bonds, which lead to different interaction combinations and solid state structures. While the bond lengths and angles in the isothiazol rings of the sultams are similar, the dihedral angles between the isothiazol rings and the hetaryl substituents are influenced by the position of the nitrogen atom in the pyridine ring and its substituents. The sultams form chain structures, dimeric head-to-tail structures or two-dimensional networks.

A novel class of dibenzo-fused 1,9-diaza-9a-boraphenalenes featuring zigzag edges with a nitrogen-boron-nitrogen bonding pattern named NBN-dibenzophenalenes (NBN-DBPs) has been synthesized. Alternating nitrogen and boron atoms impart high chemical stability to these zigzag-edged polycyclic aromatic hydrocarbons (PAHs), and this motif even allows for postsynthetic modifications, as demonstrated here through electrophilic bromination and subsequent palladium-catalyzed cross-coupling reactions. Upon oxidation, as a typical example, NBN-DBP 5a was nearly quantitatively converted to σ-dimer 5a-2 through an open-shell intermediate, as indicated by UV-vis-NIR absorption spectroscopy and electron paramagnetic resonance spectroscopy corroborated by spectroscopic calculations, as well as 2D NMR spectra analyses. In situ spectroelectrochemistry was used to confirm the formation process of the dimer radical cation 5a-2(•+). Finally, the developed new synthetic strategy could also be applied to obtain π-extended NBN-dibenzoheptazethrene (NBN-DBHZ), representing an efficient pathway toward NBN-doped zigzag-edged graphene nanoribbons.

The aromatic thioether (2,6-bis((2-(dimethylamino)ethylamino)methyl)phenyl)(tert-butyl)sulfane (6) reacts with [Pd(NCCH3)2Cl2] under S–C bond cleavage to give the dinuclear palladium(II) complex [L3Pd2(μ-Cl)]2+ (7), where (L3)− = 2,6-bis((2-(dimethylamino)ethylamino)methyl)-thiophenolate. Complex 7 reacts readily with sodium acetate and sodium acetamide by the displacement of the bridging chloride group forming [L3Pd2(μ-OAc)]2+ (8) and [L3Pd2(μ-ONHCCH3)]2+ (9), respectively. Complex 8 can also be prepared by the reaction of 6 with [Pd(OAc)2]. All complexes were isolated as perchlorate salts and fully characterized by ESI-MS, IR, 1H, and 13C NMR spectroscopy. The structures of 7[ClO4] and 9[ClO4]2 have been determined by X-ray crystallography. The latter structure reveals a μ1,3-bridging acetamidate unit showing that (L3)− can alter its conformation sufficiently to accommodate a multi-atom bridging species between the two Pd atoms.

2-Oxo-D-gluconic acid obtained by fermentation of D-glucose was used as starting material for syntheses of amino acids. We trapped the carbohydrate in its furanoid configuration and synthesized an α- and an ω-amino acid. After deprotection of the hydroxyl groups the latter did not isomerize to the substituted piperidine (aza-sugar) as expected, but remained in the furanose form. The starting structure 2 was proven by crystal structure analysis. The conformational identification of the other substances was done by NMR measurements following known rules for furanoses.

Angular structure of 3,3′,5,5′-tetramethyl-4,4′-bipyrazole tecton (Me4bpz) supports multiple helical strands in a series of coordination and hydrogen bonded polymers prepared using hydrothermal technique. Compounds reveal a variety of helical architectures and exist in the forms of double helicate Ag(Me4bpz)(PO2F2), two-dimensional network formed by inter-connection of the helices Ag2(Me4bpz)3(CF3CO2)2, interpenetrated two-dimensional networks by interconnection of double helices Ag4(Me4bpz)5(NO3)4 · 2H2O and triple helicate formed by NH‒‒‒N hydrogen bonded bipyrazole molecules in structure Me4bpz·H2O. Coordination polymers Ag(Me4bpz)X ((X = ClO4−, CF3SO3−, C2F5CO2−) adopt simpler chain-like structure. In all coordination compounds the bipyrazole acts as a bridging neutral group and connects two silver atoms at the distances of 9.44–9.94A.

Durch Umsetzung von Diethylzink mit den Aminoalkoholen 3-Dimethylaminopropanol und 2-Diethylaminomethylphenol konnten die entsprechenden oligomeren Ethylzinkaminoalkoxide I und II dargestellt werden. Im Festkorper liegt I als Trimeres und II als Dimeres vor. Nach Reaktion von Zink(II)-chlorid mit den Aminoalkoholen 2-Dimethylaminoethanol und (R/S)-1-Dimethylaminoisopropanol konnten die tetrameren Chloro-aminoalkoholato-zink(II)-Komplexe III und IV isoliert werden. Alle Verbindungen wurden durch Rontgenkristallstrukturanalyse und NMR-Spektroskopie charakterisiert.

The title compounds are prepared by high temperature/high pressure reactions of mixtures of the elements in the molar ratio RE:B:S = 1:3:6 (3.5 GPa, 1673 K, 5 h).

The orthothioborates Ce[BS{sub 3}], Pr[BS{sub 3}] and Nd[BS{sub 3}] were prepared from mixtures of the rare earth (RE) metals together with amorphous boron and sulfur summing up to the compositions CeB{sub 3}S{sub 6}, PrB{sub 5}S{sub 9} and NdB{sub 3}S{sub 6}. The following preparation routes were used: solid state reactions with maximum temperatures of 1323 K and high-pressure high-temperature syntheses at 1173 K and 3 GPa. Pr[BS{sub 3}] and Nd[BS{sub 3}] were also obtained from rare earth chlorides RECl{sub 3} and sodium thioborate Na{sub 2}B{sub 2}S{sub 5} by metathesis type reactions at maximum temperatures of 1073 K. The crystal structure of the title compounds was determined from X-ray powder diffraction data. The thioborates are isotypic and crystallize in the orthorhombic spacegroup Pna2{sub 1} (No. 33; Z=4; Ce: a=7.60738(6)A, b=6.01720(4)A, c=8.93016(6)A; Pr: a=7.56223(4)A, b=6.00876(2)A, c=8.89747(4)A; Nd: a=7.49180(3)A, b=6.00823(2)A, c=8.86197(3)A) . The crystal structures contain isolated [BS{sub 3}]{sup 3-} groups with boron in trigonal-planar coordination. The sulfur atoms form the vertices of undulated kagome nets, which are stacked along [100] according to the sequence ABAB. Within these nets every second triangle is occupied by boron and the large hexagons are centered by rare earth ions, which are surrounded by overall nine sulfur species.more » - Abstract: Graphical Abstract Legend (TOC Figure): Table of Contents Figure The isotypic orthothioborates Ce[BS{sub 3}], Pr[BS{sub 3}] and Nd[BS{sub 3}] were prepared using different preparation routes. The crystal structure of the title compounds was determined from X-ray powder diffraction data. The crystal structures contain isolated [BS{sub 3}]{sup 3-} groups with boron in trigonal-planar coordination. The sulfur atoms form the vertices of corrugated kagome nets (sketched with blue dotted lines), which are stacked along [100] according to the sequence ABAB. Within these nets every second triangle is occupied by boron and the large hexagons are centered by rare earth ions, which are surrounded by overall nine sulfur species.« less

The structural chemistry of calcium nitrides is represented by just two different intermediate phases: cubic Ca(3)N(2) (referred to as alpha-Ca(3)N(2), Mn(2)O(3) type structure) and Ca(2)N (CdCl(2) type structure). Other binary phases ("gamma-Ca(3)N(2)", "Ca(11)N(8)") have been proven to represent cyanamide nitrides, Ca(4)N(2)[CN(2)] and Ca(11)N(6)[CN(2)](2), respectively. The metastable nitride beta-Ca(3)N(2) is prepared either by reaction of freshly distilled calcium metal with nitrogen at 700 K, or by reaction of Ca(2)N with N(2) at 500 K. beta-Ca(3)N(2) transforms monotropically (T(trans) approximately 810 K) to cubic alpha-Ca(3)N(2). The crystal structure of beta-Ca(3)N(2) (rhombohedral R3c, no. 167, a=619.884(3) pm, c=1662.958(10) pm) is an isotype of the corundum structure (alpha-Al(2)O(3)) and comprises a network of NCa(6/4) octahedra that share common faces and edges. Magnetic susceptibility and electrical resistivity measurements confirm that beta-Ca(3)N(2) is a diamagnetic semiconductor.

New methods for determination of adsorbate structures in crystalline porous solids by diffraction methods have been investigated. Therefore combination and interaction of atomistic simulations with Rietveld refinement for more detailed determination of adsorbate structures based on diffraction data has been implemented within the new GUI-guided opensource software project S aass (Simulation Assisted Adsorbate Structure Solution). The main principle is the use of different configured multiple MC-MD simulations for getting trial structures for Rietveld refinement and pair distribution function (PDF) fitting after averaging and symmetry evaluation and recycling of the refined structures for finding a realistic minimum structure with low energy. The prospects of success in structure determination on the basis of this algorithm are evaluated with the relatively complex faujasite water adsorbate systems. We want to show that new insights into structural chemistry of adsorbates can be gained.

A series of metal-organic frameworks (MOF) like Zn-MOF-5, TT-1, Cd-, and Co-MOF are investigated using 129Xe NMR spectroscopy. 129Xe NMR experiments are performed over a xenon pressure range from 5 kPa to 150 kPa for studying properties of the MOF's such as the pore dimensions, geometry of the pores, coadsorbed phases, and the influence of the composition of the materials on the chemical shift of the adsorbed xenon. The differences observed in the chemical shifts values can be attributed to different types of micropores generated by the synthesis procedure and the composition of the materials.

Diffuse reflectance infrared Fourier transform spectroscopic (DRIFTS) measurements (4000-1500 cm(-1)) and the results of neutron powder diffraction have been combined to study the structure of adsorption complexes of water in a NaX zeolite at different water loadings (25, 48, 72, and 120 water molecules per unit cell, respectively). Sharp bands corresponding to non-hydrogen-bonded OH groups of water molecules and broad associate bands due to hydrogen-bonded molecules are observed in the DRIFT spectra. We observe a remarkable downshift of the high-frequency associate band in a narrow temperature interval when the water amount decreases from 120 to 72 molecules per unit cell, which could signify some kind of "phase transition" for the water inside the zeolite cavities. Neutron powder diffraction results show that water molecules are predominantly localized in or near the 12-ring windows. Water molecules with hydrogen-bonded and non-hydrogen-bonded OH groups were found, in agreement with the observation of sharp and broad bands in the DRIFT spectra. We find strong evidence for the formation of cyclic hexamers of water molecules localized in the 12-ring windows, which are further stabilized by hydrogen bonds to framework oxygen atoms.

BPrS 3 ,orthorhombic, Pna 2 1 (no. 33), a =7.5434(8) A, b =6.0130(5) A, c =8.886(1) A, V =403.1 A 3 , Z =4, R gt (F) =0.025, wR ref (F 2 ) =0.060, T =295 K. Source of material Amixture of 779.01 mg (5.528 mmol) praseodymium powder(ChemPur,99.9%),298.90mg(27.648mmol)amorphousboron(powder, ABCR, 99 %) and 1595.66 mg (49.762 mmol) sulfur(Alfa Aesar, 99.9995 %, sublimed under vacuum to reduce oxy-gen contamination below 1%)was ground, cold pressed, againgroundandfilledinaboronnitridecrucible(diameter16/10mm,height 50 mm). The crucible was deposited in asealed tantalumampoule(diameter18mm,height100mm)underambientargonpressure.DuetothesidereactionofB 2 S 3 withtantalumsomeex-cessboronandsulfurwereused.Bythis,theeductssumuptothetotal chemical composition PrB 5 S 9 .The complete reaction con-tainer wasdepositedinaquartzglassreactorwithconnectionstoargon supply and arelief pressure valve. The reaction was per-formed by using avertical tube furnace. The following tempera-tureprogramwasappliedunderconstantargonflow:298K→4

BS3Sm, orthorhombic, Pna21 (no. 33), a = 7.3657(5) A, b = 6.0272(2) A, c = 8.8004(6) A, V = 390.69 A 3 , Z =4 , R(F 2 ) = 0.068, R(P) = 0.013, T = 295 K. Source of material Sm[BS3] was prepared by using a high-temperature highpressure route. Molar ratios o f1:3:6 ofsamarium (powder, ChemPur, 99.9 %), amorphous boron (ABCR, 99 %) and sulfur (Alfa Aesar, 99.9995 %, sublimed under vacuum to reduce contamination by oxygen below 1 %) were used. Molar ratios corresponding to the chemical composition of the title compound did not yield sufficiently pure materials. The educts were ground and filled into the assembly of the octahedral high pressure setup, under argon atmosphere of a glove box. Hexagonal boron nitride was used as the crucible material. High pressure conditions were achievedbyusingahydraulicuniaxialpress[1].Forceredistribution was accomplished by a Walker-type module and MgO octahedra with an edge length of 18 mm [2]. Elevated temperatures were realized by resistive heating of graphite tubes enclosing the sample crucible. For the synthesis of Sm[BS3], the assembly was heated to 1673 K and compressed to 3 GPa for 5 h. Afterthepressureandheatingcycle,thearrangementwasinstantaneously removed and transferred into a glove box where the sample was isolated from the crucible. No indications of a reactionbetweenthesampleandthecruciblematerialwereobserved. The air- and humidity-sensitive compound Sm[BS3] was obtained as a red-brown polycrystalline material. Experimental details X-ray powder diffraction data were collected on a STOE StadiPMPdiffractometerinDebye-Scherrergeometry.TheGSASsoftware package [3] was used for the Rietveld refinements. The unit cellparametersatroomtemperatureweredeterminedfromX-ray powder diffraction data (CuK1), using LaB6(a= 4.15692(1) A) as internal standard, and refined by least squares refinements usingtheWinCSDprogram[4].Thepositionoftheboronatomwas restrainedtobenearthecentreofgravityofthesulfuratomsofthe [BS3] 3– unit. The isotropic displacement parameters of the sulfur atoms were constrained to be equal and the corresponding parameter of the boron site was constrained to be equal to that of the attached sulfur atoms. Discussion The new RE thioborate Sm[BS3], obtained as a product of the high-pressure high-temperature experiments, is an isotype of the RE[BS3] series (RE= Ce, Pr, Nd) [5,6]. The crystal structure was refinedfromX-raypowderdiffractiondatausingtheRietveldrefinement method [7]. The crystal structure of Sm[BS3] is characterized by corrugated kagome nets formed by sulfur atoms, with the boron atoms occupying every second triangle, while Sm cations center the large hexagons. The corrugated nets are stacked along [100] according to the sequence ABAB. The coordination sphereofSmisformedbyninesulfurspeciesoriginatingfromsix neighboring thioborate units. Three of the [BS3] 3– units act as bidentate ligands, while the other three are in monodentate func

Monocyclic, acceptor-substituted N-aroylisothiazolium-2-imines (5ail), easily available by cyclocondensation of 2-methyl-3-thiocyanato-2-butenal with aryl hydrazides, are described and the structure of new five-membered azomethine imines (5) is determined by X-Ray structure of 5a. The oxidation of 2-imines (5) with hydrogen peroxide in acetic acid gives 3-hydroperoxysultims (rac-cis 6), -sultams (7), and 3-oxosultams (10). The 3-hydroxysultams (8a-d) are obtained by reduction of hydroperoxides (7). Surprisingly, after the dehydration of 8a-h and its 1,5-electrocyclization, a new type of heteropentalenes, the isothiazolo[3,2-b]-1,3,4-oxadiazole-5,5-dioxides (11) is formed.

Magnetic properties of the substitution series Ru$_{1-x}$Cr$_x$Cl$_3$ were investigated to determine the evolution from the anisotropic Kitaev magnet $\alpha$-RuCl$_3$ with $J_{\rm eff} = 1/2$ magnetic Ru$^{3+}$ ions to the isotropic Heisenberg magnet CrCl$_3$ with $S = 3/2$ magnetic Cr$^{3+}$ ions. Magnetization measurements on single crystals revealed a reversal of the magnetic anisotropy under doping, which we argue to arise from the competition between anisotropic Kitaev and off-diagonal interactions on the Ru-Ru links and approximately isotropic Cr-Ru and isotropic Cr-Cr interactions. In addition, combined magnetization, ac susceptibility and specific-heat measurements clearly show the destabilization of the long-range magnetic order of $\alpha$-RuCl$_3$ in favor of a spin-glass state of Ru$_{1-x}$Cr$_x$Cl$_3$ for a low doping of $x\backsimeq0.1$. The corresponding freezing temperature as a function of Cr content shows a broad maximum around $x\backsimeq0.45$.