Neue Sesquisulfide der Lanthanoide im U2S3-Typ: Tb2S3 und Dy2S3

New sesquisulfides of the lanthanides with the U2S3-type structure (M2S3, M = Tb and Dy) were prepared through the oxidation of TbClH0,67 and DyCl2, respectively, with appropriate amounts of sulfur in the presence of NaCl fluxes in silica protected sealed tantalum containers at 850 °C for at least seven days. The preparation from the elements (2M + 3S; M = Tb and Dy) under otherwise analogous reaction conditions and temperatures was also successful when equimolar fluxes of NaCl were applied. The crystal structure was determined from single crystal data for Tb2S3 and Dy2S3, both crystallizing with the U2S3-type structure (orthorhombic, Pnma, Z = 4; Tb2S3: a = 1067.87(8), b = 388.06(4), c = 1049.07(7) pm ; Dy2S3: a = 1062.45(7), b = 386.59(4), c = 1044.36(8) pm) when prepared under the above-mentioned conditions

Synthese und Kristallstruktur von Europium(III)-diacetatotriaquo-chlorid, [Eu(CH3COO)2(H2O)3]Cl

Colourless single crystals of [Eu(CH3COO)2(H2O)3]Cl are obtained at about 5°C from a solution of EuCl3 · 6 H2O in a mixture of acetone, tetrahydrofurane and acetanhydride (1:1:2) to which a small amount of water had been added. [Eu(CH3COO)2(H2O)3]Cl crystallizes in the monoclinic system, space group P21/n (No. 14), a = 786.19(5), b = 791.86(5), c = 1768.81(13) pm; β = 98.235(6)°, R = 0.025, Rw = 0.021, Z = 4. Eu3+ is in nine-coordinate surrounding of O2-, three of which belong to water molecules and six to acetate anions (two bidentate and two monodentate). Cationic chains of the composition [Eu(CH3COO)2(H2O)3]+ are formed through further connection via acetate-oxygen atoms. These chains are stacked hexagonally parallel [100] and held together by “lonesome” Cl- anions. The chloride ions are surrounded by 4+1 aquo ligands

Oxidsulfidchloride der Lanthanide vom Typ M4OS4Cl2 (M = La–Nd)

Oxysulfide chlorides, M4OS4Cl2, of the lanthanides (M = La - Nd) are obtained upon the oxidation of the metals with sulfur in the presence of MOCl (or M2O3) and MCl3 in appropriate molar ratios. Additional NaCl or an excess of MCl3 serving as a flux provide even single crystalline material after reactions at 850 °C for seven days in sealed tantalum capsules. The crystal structure of M4OS4Cl2 (hexagonal, P63mc, no. 186, Z = 2; M = La: a = 933.19(3), c = 701.22(4) pm, c/a = 0.7514, R = RH = 0.020; M = Ce: a = 925.49(3), c = 694.13(3) pm, c/a = 0.7500; M = Pr: a = 919.72(4), c = 688.53(4) pm, c/a = 0.7486; M = Nd: a = 914.25(4), c = 683.12(4) pm, c/a = 0.7472, R = 0.022, Rw = 0.019) contains isolated O2--centered (M3+)4 tetrahedra which are surrounded by twelve S2- and six Cl-, capping vertices, edges, and faces of each tetrahedron and linking to other [OM4] units. Basically, the structure is identical to that of Ba4OCl6 if Ba2+ is substituted by M3+ and 2/3 of the CL- anions are replaced by S2- to secure charge neutrality in M4OS4Cl2. Different models for the Cl-/S2- replacement are presented on the basis of comparisons of the Madelung part of the lattice energy (MAPLE) with the MAPLE sum of the binaries (M2O3, M2S3, and MCl3)

A-type Ce2NCl3

Cerium(III) nitride chloride, Ce2NCl3, contains trans-edge connected [NCe4]9+ tetra­hedra (222 symmetry) forming chains parallel to the c axis that are separated by Cl− anions. The Ce3+ cations (..m symmetry) are each surrounded by two N3− and six Cl− anions in a bicapped trigonal prismatic coordination geometry (CN = 8)

Cs3Sm7Se12

The title compound, tricaesium hepta­samarium(III) dodeca­selenide, is setting a new starting point for realization of the channel structure of the Cs3 M 7Se12 series, now with M = Sm, Gd–Er. This Cs3Y7Se12-type arrangement is structurally based on the Z-type sesquiselenides M 2Se3 adopting the Sc2S3 structure. Thus, the structural set-up of Cs3Sm7Se12 consists of edge- and vertex-connected [SmSe6]9− octa­hedra [d Ø(Sm3+ – Se2−) = 2.931 Å], forming a rock-salt-related network [Sm7Se12]3− with channels along [001] that are apt to take up monovalent cations (here Cs+) with coordination numbers of 7 + 1 for one and of 6 for the second cation. The latter cation has a trigonal–prismatic coordination and shows half-occupancy, resulting in an impossible short distance [2.394 (4) Å] between symmetrically coupled Cs+ cations of the same kind. While one Sm atom occupies Wyckoff position 2b with site symmetry ..2/m, all other 11 crystallographically different atoms (namely 2 × Cs, 3 × Sm and 6 × Se) are located at Wyckoff positions 4g with site symmetry ..m

Scheelite-type sodium neodymium(III) ortho-oxidomolybdate(VI), NaNd[MoO4]2

Scheelite-type NaNd[MoO4]2 contains one crystallographic position (site symmetry ) for the large cations, which is mixed-occupied by Na+ and Nd3+ cations in a 1:1 molar ratio. Thus, both are surrounded by eight O atoms in the shape of a trigonal dodeca­hedron. Furthermore, the structure consists of crystallographically unique [MoO4]2− units (site symmetry ) surrounded by eight sodium and neodymium cations, which are all vertex-attached. The polyhedra around the Na+/Nd3+ cations are connected to four others via common edges, building up a three-dimensional network in whose tetra­hedral voids of O atoms the Mo6+ cations reside

RbEr2AsS7 : a rubidium-containing erbium sulfide thioarsenate(III) with (S2)2- Ligands According to RbEr2S(S2)[AsS2(S2)]

The new rubidium-containing erbium sulfide thioarsenate(III) with the structured formula RbEr2S(S2)[AsS2(S2)] was obtained from the syntheses of elemental erbium (Er), arsenic sesquisulfide (As2S3) and rubidium sesquisulfide (Rb2S3) with elemental sulfur (S) at 773 K as transparent, orange, needle-shaped crystals. RbEr2AsS7 crystallizes monoclinically in the space group C2/c with a = 2339.86(12) pm, b = 541.78(3) pm, c = 1686.71(9) pm and β = 93.109(3) ° for Z = 8. The crystal structure features complex [AsS2(S2)]3- anions with two S2- anions and a (S2)2- disulfide dumbbell coordinating end-on as ligands for each As3+ cation. Even outside the ligand sphere of As3+, S2- and (S2)2- can be found as sulfide anions. Two distinct Er3+ cations are surrounded by either nine or seven sulfur atoms. The [ErS9] polyhedra are corner- and face-connected, while the [ErS7] units share common edges, both building chains along [010]. These different chains undergo edge connectivity with each other, resulting in the formation of corrugated layers, which are held together by Rb+ in chains of condensed [RbS9] polyhedra. So, a three-dimensional network is generated, offering empty channels along [010] apt to take up the As3+ lone-pair cations. Wavelength-dispersive X-ray spectroscopy verified a molar Rb:Er:As:S ratio of approximately 1:2:1:7 and diffuse reflectance spectroscopy showed the typical f-f transitions of Er3+, while the optical band gap was found to be 2.42 eV.State of Baden-Württemberg (Stuttgart

Scheelite-type sodium neodymium(III) ortho-oxidomolybdate(VI), NaNd[MoO4]2

The crystal structure of Scheelite-type NaNd[MoO4]2 is described in the paper

Single crystals of CaNa[ReO4]3 : serendipitous formation and systematic characterization

In an attempt to crystallize Ce[ReO4]4·xH2O from aqueous solutions of equimolar amounts of Ce[SO4]2 and Ba[ReO4]2 via salt‐metathesis the serendipitous formation of colorless, transparent, rod‐shaped single crystals of CaNa[ReO4]3 was observed as a result of calcium and sodium impurities within the improperly deionized water used. Structure analysis by X‐ray diffraction lead to the conclusion that the title compound crystallizes in the ThCd[MoO4]3 structure type with the hexagonal space group P63/m and the lattice parameters a = 991.74(6) pm, c = 636.53(4) pm, c/a = 0.642 for Z = 2. The crystal structure contains purely oxygen surrounded and crystallographically unique cations, namely Ca2+ in tricapped trigonal prismatic (d(Ca-O) = 6 × 249 pm + 3 × 254 pm), Na+ in octahedral (d(Na-O) = 6 × 241 pm), and Re7+ in tetrahedral coordination (d(Re-O) = 171-173 pm). Furthermore, it was possible to yield an almost phase‐pure microcrystalline powder of the title compound from a melt of equimolar amounts of Na[ReO4] and Ca[ReO4]2 stemming from aquatically obtained precursors.Federal State of Baden-WürttembergProjekt DEA

Composition and crystal structure of SmSb2O4Cl revisited : and the analogy of Sm1.5Sb1.5O4Br

The quaternary halide‐containing samarium(III) oxidoantimonates(III) Sm1.3Sb1.7O4Cl and Sm1.5Sb1.5O4Br were synthesized through solid‐state reactions from the binary components (Sm2O3, Sb2O3 and SmX3, X = Cl and Br) at 750 °C in evacuated fused silica ampoules. They crystallize tetragonally in the space group P4/mmm, like the basically isotypic bismuthate(III) compounds SmBi2O4Cl and SmBi2O4Br, but show larger molar volumes and therefore contradict an ideal composition of “SmSb2O4X” (X = Cl and Br). Both single‐crystal X‐ray diffraction and quantitative electron‐beam microprobe analysis revealed the actual compositions of the investigated antimony(III) compounds, which can be understood as heavily Sm3+‐doped derivatives of “SmSb2O4X” hosts at the Sb3+ site. (Sm1)3+ is coordinated eightfold by oxygen atoms in the shape of a cube. The mixed‐occupied (Sb/Sm2)3+ cation has four oxygen atoms and four halide anions as neighbors forming a square antiprism. The oxygen atoms and anions establish alternating layers parallel to the ab‐plane, which alternate when stacked along [001].Projekt DEA