La3B6O13(OH): The First Acentric High-Pressure Borate Displaying Edge-Sharing BO4 Tetrahedra

La₃B₆O₁₃(OH) was obtained by a high-pressure/high-temperature experiment at 6 GPa and 1673 K. The compound crystallizes in the space group P2₁ (no. 4) with the lattice parameters a=4.785(2), b=12.880(4), c=7.433(3) Å, and β=90.36(10)°, and is built up of corner- as well as edge-sharing BO₄ tetrahedra. It represents the first acentric high-pressure borate containing these B₂O₆ entities. The compound develops borate layers of „sechser“-rings with the La³⁺ cations positioned between the layers. Single-crystal and powder X-ray diffraction, vibrational and MAS NMR spectroscopy, second-harmonic generation (SHG) and thermoanalytical measurements, as well as computational methods were used to affirm the proposed structure and the B₂O₆ entities.     

A Further Extension of Pnictide Oxide Chemistry – Synthesis and Structure of La2AuP2O

The phosphide oxide La₂AuP₂O was synthesized from lanthanum filings, dried La₂O₃, gold pieces, and ground red phosphorus in the ideal 1.33:0.33:1:2 ratio in an evacuated silica tube at 1473 K. Small single crystals were obtained by recrystallization in a NaCl/KCl flux. The structure was determined on the basis of single‐crystal X‐ray diffractometer data: new type, C2/m, a = 1537.3(3), b = 427.39(8), c = 1009.2(2) pm, β = 131.02(1) °, wR₂ = 0.046, 1102 F² values, 38 variables. La₂AuP₂O contains two striking structural motifs: The oxygen atoms are located in La₄ tetrahedra. The latter are cis‐edge‐shared forming polymeric cationic [La₂O]⁴⁺ chains. These cationic units are separated and charge‐balanced by [AuP₂]^4– polyanions which have monovalent gold in distorted trigonal planar phosphorus coordination. Two crystallographically independent phosphorus sites occur in the polyanion, i.e. isolated P^3– besides dumb‐bells P₂^4– (P2–P2 223 pm). La₂AuP₂O, which crystallizes in the form of ruby red transparent crystals, is an electron precise phosphide oxide (4La³⁺)(2Au⁺)(2P^3–)(P₂^4–)(2O^2–).     

The First Sodium Uranyl Chromate,Na4[(UO2)(CrO4)3]: Synthesis and Crystal Structure Determination

The first sodium uranyl chromate, Na₄[(UO₂)(CrO₄)₃], has been obtained by high‐temperature solid‐state reaction. The structure (triclinic, P1¯, Z = 2, a = 7.1548(3), b = 8.4420(3), c = 11.5102(5)Å, α = 80.203(1)°, β = 79.310(1)°, γ = 70.415(1)° V = 639.24(4)ų ) has been solved by direct methods and refined on the basis of F² for all unique reflections to R1 = 0.024 [calculated on the basis of 4374 unique observed reflections (‖F_o‖ 4σF)]. The structure is based on chains of composition [(UO₂)(CrO₄)₃] that are parallel to [1¯01]. The chains contain UrO₅ pentagonal bipyramids (Ur = Uranyl) that share all equatorial corners with CrO₄ tetrahedra. Cr(1)O₄ and Cr(3)O₄ tetrahedra bridge between two adjacent UrO₅ bipyramids, whereas Cr(2)O₄ tetrahedra share one corner with one UrO₅ bipyramid each. The [(UO₂)(CrO₄)₃] chains are planar and oriented parallel to (313). The Na⁺ cations provide linkage of the chains in the structure.     

Preparation and Crystal Structure of La3ReO8

The crystal structure of La₃ReO₈, prepared at 1425°C, is reported to be different from a previous result on a preparation at 900°C (BAUD et al., 1979). The high temperature modification crystallizes in the monoclinic space group P2₁/m with a = 7.757(1), b = 7.777(1), c = 5.928(1) Å, γ = 111.1°, Z = 2. The structure was solved by Patterson and Fourier methods from single crystal diffractometer data and refined to final R(F) = 0,073. The structure consists of isolated, distorted ReO₆ octahedra and double chains of edge-shared La₄O tetrahedra.     

Crystal Structure Determination of Tetrabarium‐digalliumoxide,Ba4Ga2O7

Single crystals of a new barium oxogallate were obtained by growth from a melt at 1500 °C. The compound is monoclinic, with cell parameters a = 17.7447(10) Å, b = 10.6719(5) Å, c = 7.2828(5) Å, β = 98.962(7)°, V = 1362.3(2) ų. The diffraction pattern shows systematic absences corresponding to the space group P12₁/c1. The structure was solved by direct methods followed by Fourier syntheses, and refined using a single crystal diffraction data set (R1 = 0.032 for 2173 reflections with I > 2σ(I)). The chemical composition derived from structure solution is Ba₄Ga₂O₇, with a unit cell content of Z = 6. Main building units of the structure are GaO₄ tetrahedra sharing one oxygen atom to form Ga₂O₇ groups. The Ga–O–Ga bridging angle of one of the two symmetrically independent groups is linear by symmetry. The dimers are crosslinked by barium cations coordinated by six to eight oxygen ligands.     

MH4P6N12 (M=Mg,Ca): New Imidonitridophosphates with an Unprecedented Layered Network Structure Type

Isotypic imidonitridophosphates MH₄P₆N₁₂ (M=Mg, Ca) have been synthesized by high‐pressure/high‐temperature reactions at 8 GPa and 1000 °C starting from stoichiometric amounts of the respective alkaline‐earth metal nitrides, P₃N₅, and amorphous HPN₂. Both compounds form colorless transparent platelet crystals. The crystal structures have been solved and refined from single‐crystal X‐ray diffraction data. Rietveld refinement confirmed the accuracy of the structure determination. In order to quantify the amounts of H atoms in the respective compounds, quantitative solid‐state ¹H NMR measurements were carried out. EDX spectroscopy confirmed the chemical compositions. FTIR spectra confirmed the presence of NH groups in both structures. The crystal structures reveal an unprecedented layered tetrahedral arrangement, built up from all‐side vertex‐sharing PN₄ tetrahedra with condensed dreier and sechser rings. The resulting layers are separated by metal atoms.     

Synthesis and Characterization of the New Copper Indium Phosphate Cu8In8P4O30

The system CuO/In₂O₃/P₂O₅ has been investigated using solid state reaction between CuO, In₂O₃ and (NH₄)₂HPO₄ in silica glass crucibles at 900 °C. The powder samples were characterized by X‐ray diffraction, thermal analysis and FT‐IR spectroscopy. Orange single crystals of the new quaternary phase were achieved by the process of crystallization with mineralizers in sealed silica glass ampoules. They were then analyzed with EDX and single‐crystal X‐ray analysis in which the composition Cu₈In₈P₄O₃₀ with the triclinic space group P$\bar{1}$ (No 2) with a = 7,2429(14) Å, b = 8,8002(18) Å, c = 10,069(2) Å, α = 103,62(3)°, β = 106,31(3)°, γ = 101,55(3)° and Z = 1 was found. The three‐dimensional framework consists of [InO₆] octahedra and distorted [CuO₆] octahedra, overcaped [InO₇] prisms and [PO₄] tetrahedra, also trigonal [(CuIn)O₅] bipyramids and distorted [(CuIn)O₆] octahedra, where copper and indium are partly exchanged against each other. Cu₈In₈P₄O₃₀ exhibits an incongruent melting point at 1023 °C.     

Synthesis and Crystal Structure of [C10N2H10]2[P2Mo5O21(OH)2]·2H2O

The crystal structure of [C₁₀N₂H₁₀]₂[P₂Mo₅O₂₁(OH)₂] · 2H₂O, contains the heteropolyanion, [P₂Mo₅O₂₁(OH)₂]^4—, together with diprotonated 4, 4′‐bipyridine. The heteropolyanion is built up from five MoO₆ octahedra sharing four common edges and one common corner, capped by two PO₃(OH) tetrahedra. The structure is stabilized by hydrogen bonds involving the hydrogen atoms of the 4, 4′‐bipyridine, water molecules and the oxygen atoms of the pentamolybdatobisphosphate. This is the first example that this kind of cluster could be isolated in the presence of a poly‐functional aromatic molecule ion. Crystal data: triclinic, P1¯ (No. 2), a = 9.983(2)Å, b = 11.269(2)Å, c = 17.604(4)Å, α = 73.50(3)°, β = 84.07(3)°, γ = 67.96(3)°; V = 1760.0(6)ų; Z = 2; R₁ = 0.037 and wR₂ = 0.081, for 9138 reflections [I > 2σ(I)].     

Lanthanum (Oxo)nitridosilicates: From Ordered to Disordered Crystal Structures

The homeotypic compounds La_16.32Ba_1.82Sr_7.86[Si₆₀N_92.32O_3.68]O₁₂ and La_13.68Sr_12.32[Si₆₀N₉₆]F_6.32O_5.68 were synthesized at high temperature (1600/1500 °C) in a radio‐frequency furnace. The crystal structures [I$\bar{4}$ m (no. 217), Z = 1, a = 13.3360(10)/13.3258(10) Å and V = 2371.8(5)/2366.4(5) ų] were solved and refined on basis of single‐crystal X‐ray diffraction data and were corroborated by lattice‐energy calculations (Madelung part of lattice energy, MAPLE) powder X‐ray diffraction data and FTIR spectroscopy. They consist of a three‐dimensional network of allside corner sharing SiN_4–xO_x tetrahedra. The framework is characterized by double dreier rings. La_16.32Ba_1.82Sr_7.86[Si₆₀N_92.32O_3.68]O₁₂ represents an oxonitridosilicate oxide and La_13.68Sr_12.32[Si₆₀N₉₆]F_6.32O_5.68 a nitridosilicate fluoride oxide, as the crystal structures contain non‐condensed (O^[0]/O,F^[0]) anions. The first compound is isotypic to Sr₃Ln₁₀Si₁₈Al₁₂O₁₈N₃₆ (Ln = Ce, Pr, Nd; Z = 2), whereas the latter describes a disordered model of the crystal structure, which is homeotypic to the mentioned SiAlONs.     

The synthesis and structure of La5Pb3Z,Z  N,O. Interstitial derivatives of a Cr5B3-Type structure

Suitable proportions of La, La₄Pb₃ and La₂O₃ or LaN reacted in pressed pellets at 1050°–1250°C result in high yields of the title compounds. Single crystal X-ray studies of the oxide show it to be an isopointal, interstitial derivative of the Cr₅B₃ structure (I4/mcm, Z = 4, a = 8.6895(2) Å, c = 14.540(1) Å, R/R_w = 3.0/3.5%). Oxygen or nitrogen atoms are bound in (La2)₄ tetrahedra within chains along (0, 1 /2, z). Negligible dimerization of the type characteristic of Cr₅B₃ is indicated by the Pb2? Pb2 separation, 3.550(1) Å. The structure is compared with other related examples.     

SrP3N5O: a highly condensed layer phosphate structure solved from a nanocrystal by automated electron diffraction tomography

The oxonitridophosphate SrP₃N₅O has been synthesized by heating a multicomponent reactant mixture that consisted of phosphoryl triamide OP(NH₂)₃, thiophosphoryl triamide SP(NH₂)₃, SrS, and NH₄Cl enclosed in evacuated and sealed silica‐glass ampoules up to 750 °C. The compound was obtained as nanocrystalline powder with needle‐shaped crystallites. The crystal structure was solved ab initio on the basis of electron diffraction data by means of automated electron diffraction tomography (ADT) and verified by Rietveld refinement with X‐ray powder diffraction data. SrP₃N₅O crystallizes in the orthorhombic space group Pnma (no. 62) with unit‐cell data of a=18.331(2), b=8.086(1), c=13.851(1) Å and Z=16. The compound is a highly condensed layer phosphate with a degree of condensation κ=1/2. The corrugated layers ${{{\hfill 2\atop \hfill \infty }}}The oxonitridophosphate SrP(3)N(5)O has been synthesized by heating a multicomponent reactant mixture that consisted of phosphoryl triamide OP(NH(2))(3), thiophosphoryl triamide SP(NH(2))(3), SrS, and NH(4)Cl enclosed in evacuated and sealed silica-glass ampoules up to 750 °C. The compound was obtained as nanocrystalline powder with needle-shaped crystallites. The crystal structure was solved ab initio on the basis of electron diffraction data by means of automated electron diffraction tomography (ADT) and verified by Rietveld refinement with X-ray powder diffraction data. SrP(3)N(5)O crystallizes in the orthorhombic space group Pnma (no. 62) with unit-cell data of a=18.331(2), b=8.086(1), c=13.851(1) ? and Z=16. The compound is a highly condensed layer phosphate with a degree of condensation κ=?. The corrugated layers (∞)(2){(P(3)N(5)O)(2-)} consist of linked, triangular columns built up from P(O,N)(4) tetrahedra with 3-rings and triply binding nitrogen atoms. The Sr(2+) ions are located between the layers and exhibit six-, eight-, and ninefold coordination. FTIR and solid-state NMR spectra of SrP(3)N(5)O are discussed as well.     

La2Si2O7 im I—Typ: Gemäß La6[Si4O13][SiO4]2 kein echtes Lanthandisilicat

I‐Type La₂Si₂O₇: According to La₆[Si₄O₁₃][SiO₄]₂ not a Real Lanthanum Disilicate In attempts to synthesize lanthanum telluride silicate La₂Te[SiO₄] (from La, TeO₂, SiO₂ and CsCl, molar ratio: 1 : 1: 1 : 20, 950 °C, 7 d) or fluoride‐rich lanthanum fluoride silicates (from LaF₃, La₂O₃, SiO₂ and CsCl, molar ratio: 5 : 2 : 3 : 17, 700 °C, 7 d) in evacuated silica tubes, colourless lath‐shaped single crystals of hitherto unknown I‐type La₂Si₂O₇ (monoclinic, P2₁/c; a = 726.14(5), b = 2353.2(2), c = 1013.11(8) pm, β = 90.159(7)°) were found in the CsCl‐flux melts. Nevertheless, this new modification of lanthanum disilicate does not contain any discrete disilicate groups [Si₂O₇]^6‐ but formally three of them are dismutated into one catena‐tetrasilicate ([Si₄O₁₃]^10‐ unit of four vertex‐linked [SiO₄]^4‐ tetrahedra) and two ortho‐silicate anions (isolated [SiO₄]^4‐ tetrahedra) according to La₆[Si₄O₁₃][SiO₄]₂. This compound can be described as built up of alternating layers of these [SiO₄]^4‐ and the horseshoe‐shaped [Si₄O₁₃]^10‐ anions along [010]. Between and within the layers the high‐coordinated La ³⁺ cations (CN = 9 ‐ 11) are localized. The close structural relationship to the borosilicates M₃[BSiO₆][SiO₄](M = Ce ‐ Eu) is discussed and structural comparisons with other catena‐tetrasilicates are presented.     

Three N2‐benzoyl­oxybenz­amidines: sheet structures built from hard and soft hydrogen bonds and aromatic π–π stacking interactions

Molecules of the title compounds N²‐(benzoyl­oxy)­benz­ami­dine, C₁₄H₁₂N₂O₂, (I), N²‐(2‐hydroxy­benzoyl­oxy)­benz­ami­dine, C₁₄H₁₂N₂O₃, (II), and N²‐benzoyloxy‐2‐hydroxybenzamidine, C₁₄H₁₂N₂O₃, (III), all have extended chain conformations, with the aryl groups remote from one another. In (I), the mol­ecules are linked into chains by a single N—H⋯N hydrogen bond [H⋯N = 2.15 Å, N⋯N = 3.029 (2) Å and N—H⋯N = 153°] and these chains are linked into sheets by means of aromatic π–π stacking interactions. There is one intramolecular O—H⋯O hydrogen bond in (II), and a combination of one three‐centre N—H⋯(N,O) hydrogen bond [H⋯N = 2.46 Å, H⋯O = 2.31 Å, N⋯N = 3.190 (2) Å, N⋯O = 3.146 (2) Å, N—H⋯N = 138° and N—H⋯O = 154°] and one two‐centre C—H⋯O hydrogen bond [H⋯O = 2.46 Å, C⋯O = 3.405 (2) Å and C—H⋯O = 173°] links the mol­ecules into sheets. In (III), an intramolecular O—H⋯N hydrogen bond and two N—H⋯O hydrogen bonds [H⋯O = 2.26 and 2.10 Å, N⋯O = 2.975 (2) and 2.954 (2) Å, and N—H⋯O = 138 and 163°] link the molecules into sheets.     

Bilayers in 4‐iodo‐N‐(2‐iodo‐4‐nitrophenyl)benzamide generated by a combination of an N—H⋯O=C hydrogen bond and two independent iodo–nitro interactions

Molecules of the title compound, C₁₃H₈I₂N₂O₃, are linked into C(4) chains by a single N—H⋯O=C hydrogen bond [H⋯O = 2.10 Å, N⋯O = 2.832 (5) Å and N—H⋯O = 140°]. Two independent two‐centre iodo–nitro interactions, both involving the same O atom but different I atoms [I⋯O = 3.205 (3) and 3.400 (3) Å, and C—I⋯O = 160.4 (2) and 155.7 (2)°], link the hydrogen‐bonded chains into bilayers.     

Synthesis and Structure of the New Compound La2O(CN2)2 Possessing an Interchanged Anion Proportion Compared to the Parent La2O2(CN2). Synthese und Kristallstruktur der neuen Verbindung La2O(CN2)2 mit einem vertauschten Anionenverhältnis gegenüber der Bezugsverbindung La2O2(CN2)

La₂O(CN₂)₂ was synthesized from a 1:1:2 molar reaction mixture of LaCl₃, LaOCl, and Li₂(CN₂) at 650 °C. Well developed single crystals were grown from a LiCl‐KCl flux. The crystal structure was refined as monoclinic (space group C2/c, Z = 2, a = 13.530(2) Å, b = 6.250(1) Å, c = 6.1017(9) Å, β = 104.81(2)°) from single crystal X‐ray diffraction data. The La³⁺ and (CN₂)^2— ions in the crystal structure of La₂O(CN₂)₂ can be compared to Fe³⁺ and S₂^2— ions in the cubic pyrite structure, being arranged like in a distorted NaCl type structure with their centers of gravity. In addition, the O^2— ions in La₂O(CN₂)₂ are occupying 1/4 of the tetrahedral voids formed by the arrangement of metal ions.     

Die neuen Schichtsilicate Ba3Si6O9N4 und Eu3Si6O9N4

The New Layer‐Silicates Ba₃Si₆O₉N₄ and Eu₃Si₆O₉N₄ The new oxonitridosilicate Ba₃Si₆O₉N₄ has been synthesized in a radiofrequency furnace starting from BaCO₃, amorphous SiO₂ and Si₃N₄. The reaction temperature was at about 1370 °C. The structure of the colorless compound has been determined by single‐crystal X‐ray diffraction analysis (Ba₃Si₆O₉N₄, space group P3 (no. 143), a = 724.9(1) pm, c = 678.4(2) pm, V = 308.69(9)· 10⁶ pm³, Z = 1, R1 = 0.0309, 1312 independent reflections, 68 refined parameters). The compound is built up of corner sharing SiO₂N₂ tetrahedra forming corrugated layers between which the Ba²⁺ ions are located. Substitution of barium by europium leads to the isotypic compound Eu₃Si₆O₉N₄. Because no single‐crystals could be obtained, a Rietveld refinement of the powder diffractogram was conducted for the structure refinement (Eu₃Si₆O₉N₄, space group P3 (no. 143), a = 711.49(1) pm, c = 656.64(2) pm, V = 287.866(8) ·10⁶ pm³, R_p = 0.0379, R_F² = 0.0638). The ²⁹Si MAS‐NMR spectrum of Ba₃Si₆O₉N₄ shows two resonances at ?64.1 and ?66.0 ppm confirming two different crystallographic Si sites.     

Complex Topology of Uranyl Polyphosphate Frameworks: Crystal Structures of α‐, β‐K[(UO2)(P3O9)] and K[(UO2)2(P3O10)]

Three new uranyl polyphosphates, α‐K[(UO₂)(P₃O₉)] ( 1 ), β‐K[(UO₂)(P₃O₉)] ( 2 ), and K[(UO₂)₂(P₃O₁₀)] ( 3 ), were prepared by high‐temperature solid‐state reactions. The crystal structures of the compounds have been solved by direct methods: 1 – monoclinic, P2₁/m, a = 8.497(1), b = 15.1150(1), c = 14.7890(1) Å, β = 91.911(5)°, V = 1898.3(3) ų, Z = 4, R₁ = 0.0734 for 4181 unique reflections with |F₀| ≥ 4σ_F; 2 – monoclinic, P2₁/n, a = 8.607(1), b = 14.842(2), c = 14.951(1) Å, β = 95.829(5)°, V = 1900.0(4) ų, Z = 4, R₁ = 0.0787 for 3185 unique reflections with |F₀| ≥ 4σ_F; 3 – Pbcn, a = 10.632(1), b = 10.325(1), c = 11.209(1) Å, V = 1230.5(2) ų, Z = 4, R₁ = 0.0364 for 1338 unique reflections with |F₀| ≥ 4σ_F. In the structures of 1 and 2 , phosphate tetrahedra share corners to form infinite [PO₃]^? chains, whereas, in the structure of 3 , tetrahedra form linear [P₃O₁₀]^5? trimers. The structures are based upon 3‐D frameworks of U and P polyhedra linked by sharing common O corners. The infinite [PO₃]^? chains in the structures of 1 and 2 are parallel to [100] and [–101], respectively. The uranyl polyphosphate frameworks are occupied by host K⁺ cations.     

RbFe[BP2O8(OH)]: Ein neues Borophosphat mit offen-verzweigten Vierer-Einfach-Tetraederketten

RbFe[BP₂O₈(OH)]: A New Borophosphate Containing Open-Branched Tetrahedral Vierer-Einfach Chains RbFe[BP₂O₈(OH)] is formed under mild hydrothermal conditions (T = 165–170 °C) from a mixture of RbOH_(aq), FeCl₂ · 4 H₂O, H₃BO₃ and H₃PO₄. The crystal structure of the monoclinic compound was solved by x-ray single crystal methods (space group P2₁/c, No. 14): a = 935.8(5) pm, b = 833.9(6) pm, c = 965.6(5) pm; β = 101.69(4)°; Z = 4. The anionic partial structure contains open-branched vierer-einfach chains [BP₂O₈(OH)]^4–, which are formed by alternating borate and phosphate tetrahedra sharing common corners. Fe³⁺ is in an octahedral coordination (FeO₅(OH)), while Rb⁺ is irregularly coordinated by ten oxygen-functions of neighbouring tetrahedra.     

Synthesis and crystal structure of a new polynuclear complex with a monomer of (3,4,9,10-dibenzo-1,12-diaza-5,8-dioxacyclopentadecane)-copper(II) (μ-C1)2 zinc(II) chloride

A polynuclear complex containing a monomer of Cu(II)-Zn(II) heterobinuclear unit was synthesized and characterized by IR spectra and magnetic moment. The crystal and molecular structure of the complex, CuZnC₁₉H₂₄Cl₄N₂O₂, was determined by X-ray diffraction, it crystallized in monoclinic, P2₁/m, α = 8.812 (2), b = 15.972(3), c = 8.831(1) Å, β = 114.33(1)^°, V = 1132.4ų, Z = 2, D_e = 1.710 g/ cm³,γ(MoK_α) =0.71073 å, μ = 25.227 cm^?1, R = 0.051. R_w = 0.063 for 1130 observed reflections with I>3α(1). The coordinated octahedra of Cu(II) and tetrahedra of Zn(II) via bridging CI atoms form a single chain polynuclear complex. The Cu, Zn and bridging Cl atoms are located on the crystallographic symmetry plane m which is perpendicular to 2N and 2O donor plane.