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1.
The metal‐rich indides Ca2Pd2In and Ca2Pt2In were synthesised from the elements in sealed tantalum ampoules in an induction furnace. Both samples were investigated by X‐ray powder and single crystal diffraction: HT‐Pr2Co2Al type, C2/c, a = 1017.6(5), b = 574.1(3), c = 812.7(3) pm, β = 104.54(2)°, wR2 = 0.0344, 590 F2 values for Ca2Pd2In and a = 1004.3(3), b = 568.9(1), c = 813.1(2) pm, β = 104.25(2)°, wR2 = 0.0435, 654 F2 values for Ca2Pt2In with 25 variables per refinement. The structure contain Pd2 (272 pm) and Pt2 (264 pm) dumb‐bells with a trigonal prismatic coordination for each transition metal atom. These AlB2 related slabs are condensed via common edges. Together the palladium and indium atoms build up three‐dimensional [Pd2In] and [Pt2In] polyanionic networks in which the calcium atoms fill larger channels. The bonding of calcium to the network proceeds via shorter Ca–Pd and Ca–Pt contacts. Ca2Pd2In and Ca2Pt2In are Pauli paramagnets.  相似文献   

2.
La3Au4In7 was prepared by arc‐melting of the elements and subsequent annealing at 970 K. X‐ray diffraction of powders and single crystals yielded I2/m11, mI28, a = 460.42(5) pm, b = 1389.5(1) pm, c = 1039.6(2) pm, α = 90.77(1)°, wR2 = 0.0621, 1089 F2 values, 46 variables. The structure of La3Au4In7 is of a new type. It may be considered as a monoclinically distorted, ordered variant of the La3Al11 type. The structural relation with the family of BaAl4 related compounds is discussed on the basis of a group‐subgroup scheme. The gold and indium atoms in La3Au4In7 build a three‐dimensional [Au4In7] polyanion in which the lanthanum atoms fill distorted pentagonal and hexagonal channels. Within the polyanion short Au–In and In–In distances are indicative of strongly bonding Au–In and In–In interactions.  相似文献   

3.
The ternary indium compounds Gd3Pt4In12 and Tb3Pt4In12 were synthesized from an indium flux. Arc‐melted precursor alloys with the starting compositions ∼GdPtIn4 and ∼TbPtIn4 were annealed with a slight excess of indium at 1200 K followed by slow cooling (5 K/h) to 870 K. Both compounds were investigated by X‐ray powder diffraction: a = 990.5(1), c = 1529.5(3) pm for Gd3Pt4In12 and a = 988.65(9), c = 1524.0(1) pm for Tb3Pt4In12. The structure of the gadolinium compound was solved and refined from single crystal X‐ray data: Pm1, wR2 = 0.0470, 1469 F2 values and 62 variable parameters. Both crystallographically different platinum sites have a slightly distorted trigonal prismatic indium coordination. These [PtIn6] prisms are condensed via common edges and corners forming a complex three‐dimensional [Pt12In32] network. The gadolinium, In1 and In7 atoms fill cavities within this polyanion. Tb3Pt4In12 is isotypic with the gadolinium compound.  相似文献   

4.
New Polynuclear Indium Nitrogen Compounds – Synthesis and Crystal Structures of [In4X4(NtBu)4] (X = Cl, Br, I) and [In3Br4(NtBu)(NHtBu)3] The reaction of the indium trihalides InX3 (X = Cl, Br, I) with LiNHtBu in THF leads to the In4N4‐heterocubanes [In4X4(NtBu)4] (X = Cl 1 , Br 2 , I 3 ). Additionally [In3Br4(NtBu)(NHtBu)3] ( 4 ) was obtained as a by‐product in the synthesis of 2 . 1 – 4 have been characterized by x‐ray crystal structure analysis. 1 – 3 consist of In4N4 heterocubane cores with an alternating arrangement of In and N atoms. The In atoms are coordinated nearly tetrahedrally by three N‐atoms and a terminal halogen atom. 4 contains a tricyclic In3N4 core which can be formally derived from an In4N4‐heterocubane by removing one In atom.  相似文献   

5.
A new phase has been prepared by methanolothermal reaction of Cs2CO3, BiCl3 and Li3AsSe3 at 130 °C for 36 hours. Cs4BiAs3Se7 ( I ) reveals the first Bi‐selenoarsenate polyanionic chain [Bi(As2Se4)(AsSe3)]4–, consisting of Bi3+ ions in a distorted octahedral environment of [AsSe3]3– and trans‐[As2Se4]4– units. The latter anion consists of a central “As24+” dumb‐bell whereby two Se atoms are attached to each of the As atoms. Structural Data: Space Group P21/n, a = 13.404(4) Å, b = 23.745(8) Å, c = 13.880(4) Å, β = 99.324(6)°, Z = 8.  相似文献   

6.
A new binary phase, Cu10In7, was found during the investigation of the η‐phase field in the Cu‐In system. Single crystals of Cu10In7 were grown from a melt under an inert atmosphere. The compound crystallizes in the monoclinic space group C2/m with cell parameters a = 13.8453(2) Å, b = 11.8462(1) Å, c = 6.7388(1) Å and β = 91.063(1). The structure is based on a unit of face‐sharing octahedra consisting of five Cu4In2 octahedra terminated by Cu5In octahedra at both ends. The crystal structure is closely related to the Cu11In9 structure type.  相似文献   

7.
8.
9.
Ca3Au6.61Ga4.39 was synthesized by reacting the elements in a glassy carbon crucible under argon in a water‐cooled sample chamber in a high‐frequency furnace. The compound crystallizes with a new hexagonal structure type, space group P63/mmc: Z = 2, a = 926.6(2), c = 733.1(2) pm, wR2 = 0.0832, 328 F values and 20 variables. This structure type consists of a remarkably complex three‐dimensional [Au6.61Ga4.39] network with significant Au–Au, Au–Ga, and Ga–Ga interactions. The calcium atoms are located within slightly distorted hexagonal channels of the gold–gallium network. The structural relations to the AlB2 and Er2RhSi3 type structures are discussed.  相似文献   

10.
Polycrystalline samples of the isotypic quaternary compounds RENi2Ga3In (RE = Y, Gd – Tm) were obtained by arc‐melting of the elements. Crystals of the gadolinium compound were found by slow cooling of an arc‐melted button of the initial composition “GdNiGa3In”. All samples were characterized by powder X‐ray diffraction. The structure of GdNi2Ga2.89In1.11 was refined from single‐crystal X‐ray diffractometer data: new type, Pnma, a = 2426.38(7), b = 418.17(2), c = 927.27(3) pm, wR2 = 0.0430, 1610 F2 values and 88 variables. Two of the six crystallographically independent gallium sites show a small degree of Ga/In mixing. The nickel atoms show tricapped trigonal prismatic coordination by gadolinium, gallium, and indium. Together, the nickel, gallium, and indium atoms build up a complex three‐dimensional [Ni2Ga3In]δ network, which leaves cages for the gadolinium atoms. The indium atoms form zigzag chains with In–In distances of 337 pm. The crystal chemical similarities of the polyhedral packing in the GdNi2Ga3In and La4Pd10In21 structures are discussed.  相似文献   

11.
Single phase SrPtIn, Sr2Pt3In4 and Ca2Au3In4 were prepared by high-frequency melting of the elements in water-cooled glassy carbon crucibles. X-ray diffraction of powders and single crystals yielded Pnma, oP12, a = 758.57(9) pm, b = 451.52(6) pm, c = 846.0(2) pm, wR2 = 0.0937, 467 F2 values, 20 variables for SrPtIn, P62m, hP36, a = 1465.9(2) pm, c = 448.24(6) pm, wR2 = 0.0722, 1059 F2 values, 44 variables for Sr2Pt3In4 and Pnma, oP36, a = 1463.6(4) pm, b = 443.23(9) pm, c = 1272.3(2) pm, wR2 = 0.0694, 1344 F2 values, 56 variables for Ca2Au3In4. SrPtIn adopts the TiNiSi type structure. The indium atoms have a distorted tetrahedral platinum coordination. These InPt4/4 tetrahedra are edge- and corner-shared, forming a three-dimensional [PtIn] polyanion in which the strontium atoms are embedded. Sr2Pt3In4 crystallizes with the Hf2Co4P3 type structure with the more electronegative platinum atoms occupying the phosphorus sites while the indium atoms are located on the cobalt positions. Ca2Au3In4 is a new site occupancy variant of the YCo5P3 type. Gold atoms occupy the phosphorus sites and indium the cobalt sites, but one cobalt site is occupied by calcium atoms leading to the composition Ca2Au3In4. Common geometrical motifs of both structures are condensed, platinum(gold)-centered trigonal prisms formed by the alkaline earth and indium atoms. The platinum (gold) and indium atoms form complex three-dimensional [Pt3In4] and [Au3In4] polyanions, respectively. The alkaline earth cations are located in distorted hexagonal tubes.  相似文献   

12.
13.
The reactions of Au(OH)3, M2CO3 (M = Li, Na, Rb), and methanesulfonic acid at elevated temperatures in sealed glass ampoules lead to single crystals of M[Au(CH3SO3)4] (M = Li, Na, Rb). In the crystal structures of Li[Au(CH3SO3)4] (tetragonal, I$\bar{4}$ , Z = 2,a = 938.64(2) pm, c = 917.01(3) pm, V = 807.93(4) Å3) and Rb[Au(CH3SO3)4] (tetragonal, P$\bar{4}$ 21c, Z = 2, a = 946.7(1) pm,c = 889.9(1) pm, V = 797.6(2) Å3) the complex aurate anions are linked by the M+ ions in three dimensions. Contrastingly, in the structure of Na[Au(CH3SO3)4] (triclinic, P$\bar{4}$ , Z = 1, a = 540.04(2) pm,b = 863.75(2) pm, c = 973.29(3) pm, α = 72.694(2)°, β = 75.605(2)°, γ = 77.687(2)°, V = 415.05(2) Å3) the complex anions are connected into layers that are further connected by weak hydrogen bonds. The thermal decomposition of Li[Au(CH3SO3)4] was monitored up to 500 °C and leads in a multi‐step process to elemental gold and Li2SO4.  相似文献   

14.
The magnesium‐rich intermetallic compound Nd4.67Ru3Mg8.83 was synthesized from the elements in a sealed tantalum tube in a resistance furnace. Nd4.67Ru3Mg8.83 was characterized by X‐ray powder and single crystal diffraction: new structure type,I4/mmm, tI66, a = 946.0(1), c = 1789.5(4) pm, wR2 = 0.0368, 725 F2 values and 36 variables. Two of the five crystallographically independent magnesium sites show a small degree of Mg/Nd mixing. The ruthenium atoms have square anti‐prismatic Nd4Mg4 coordination. Always six of such anti‐prisms are condensed via common edges, leading to a CsCl analogous neodymium coordination for the Mg4 atoms. The two‐dimensional networks of edge‐sharing Ru@Nd4Mg4 antiprisms are condensed to a three‐dimensional network via Mg5@Mg34Mg14 cubes. The extended magnesium substructure shows a broad range of Mg–Mg distances from 308 to 351 pm.  相似文献   

15.
The Copper Iridium Boride Cu2Ir4B3 with a Layer Structure Derived from the ZnIr4B3 Type The new compound Cu2Ir4B3 (orthorhombic, Cmcm, a = 283.21(2) pm, b = 2540.6(1) pm, c = 281.06(2) pm, Z = 2, 209 reflexions, 18 parameters, R = 0.043) was prepared by reaction of the elements. The structure is related to the ZnIr4B3 type. It contains slabs composed of Ir6B‐ und Ir6‐prisms which alternate with copper double layers.  相似文献   

16.
Single crystals of the new title compounds are prepared from the elements (Ar, 1250—1450 °C, 1—6 h) and their structures are determined by single crystal XRD.  相似文献   

17.
18.
The intermetallic compounds CeRhIn4?xMgx (x = 0.79 and 0.84) were prepared from the elements in sealed tantalum ampoules in a high‐frequency furnace. The samples were investigated by X‐ray powder and single crystal diffraction: LaCoAl4 type, Pmma, a = 829.5(2), b = 433.56(9), c = 740.2(2) pm, wR2 = 0.0458, 651 F2 values, 25 variables for CeRhIn3.21Mg0.79 and a = 831.44(10), b = 433.49(10), c = 741.04(10) pm, wR2 = 0.0543, 915 F2 values, 25 variables for CeRhIn3.16Mg0.84. The indium atoms build up two‐dimensional networks perpendicular to the b axis in an AA stacking sequence leaving slightly distorted trigonal, square and pentagonal prismatic voids for the rhodium, magnesium, and cerium atoms. Both square prismatic voids show small magnesium/indium mixing. The shortest interatomic distances occur for the Rh–Mg contacts (257 pm). Together, the rhodium, indium, and magnesium atoms build up three‐dimensional [RhIn4?xMgx] networks in which the cerium atoms fill distorted pentagonal channels.  相似文献   

19.
20.
Synthesis of Dimethoxyethane and Tetrahydrofuran Complexes of Rare‐Earth Nitrates – Solid State Structure of Pr(NO3)3(thf)4 The solvated rare‐earth nitrates Ln(NO3)3(thf)n (Ln = Pr, n = 4 ( 1 ); Ln = Ho ( 2 ), Yb ( 3 ), n = 3 and Ln(NO3)3(dme)2; Ln = Pr ( 4 ), Ho ( 5 )) were obtained from Ln(NO3)3(H2O)x and HC(OCH3)3. Pale green thermally labile crystals of 1 were characterized by X‐ray crystallography. The praseodymium atoms in two independent monomeric molecules show capped trigonal prismatic and pentagonal bipyramidal coordination, respectively.  相似文献   

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