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Single crystals of SrIr9In18 were obtained by induction melting of the elements in a glassy carbon crucible followed by annealing at 1070 K. SrIr9In18 was structurally characterized by X‐ray powder and single crystal diffraction: P4m2, a = 811.21(5), c = 854.49(5) pm, wR2 = 0.0511, 1223 F2 values, and 46 variables. The structure is of a new type. The basic building units are Ir@In8 (distorted square‐prismatic, square anti‐prismatic and bicapped trigonal prismatic coordination) and Ir@In9 (distorted trigonal prismatic coordination) polyhedra, which condense to a three‐dimensional network, which leaves large cavities for the strontium cations, which are coordinated to four iridium and twelve indium atoms. The [Ir9In18]2– polyanionic network is stabilized through Ir–In (267–290 pm) and In–In (302–354 pm) bonding. [ABSTRACT FROM AUTHOR]

The equiatomic gallides REAuGa (RE = La, Ce, Pr, Nd, Sm) were synthesized from the elements by arc‐melting. Small single crystals were grown by slowly cooling the samples from 1073 K to room temperature at a rate of 3 K·h–1. The REAuGa structures were reinvestigated from single‐crystal X‐ray diffractometer data. The five gallides adopt the non‐centrosymmetric EuAuGe type structure, space group Imm2, a superstructure variant of KHg2. The symmetry reductions lead to the formation of trillings and inversion twins. The domain ratios were precisely determined from the single crystal data. The striking structural motifs of the REAuGa structures are slightly puckered Au3Ga3 layers with strong covalent Au–Ga bonding. Stacking of these layers in AA′ sequence (A and A′ are related by mirror planes) leads to weak Au–Au (aurophilic bonding) and Ga–Ga interlayer interactions (319 and 283 pm in SmAuGa). Temperature dependent magnetic susceptibility measurements revealed Curie–Weiss behavior for CeAuGa and NdAuGa, whereas SmAuGa exhibits the typical van Vleck paramagnetism caused by contributions of the excited states. Antiferromagnetic ground states were observed for CeAuGa, NdAuGa, and SmAuGa below the respective Néel temperatures of 2.8, 9.5 and 24.1 K. LaAuGa is Pauli paramagnetic. [ABSTRACT FROM AUTHOR]

The lutetium‐rich indide Lu13Ni6In was synthesized from the elements by arc‐melting and subsequent annealing in a sealed niobum container. At room temperature, the Lu13Ni6In structure is centrosymmetric, space group R3m, a = 919.74(10), c = 1828.9(2) pm, wR2 = 0.0996, 666 F2 values, 43 variables. It exhibits strong anisotropic displacement parameters U33 for the Lu1 and U22 for the Ni atoms. In going to low‐temperature, Lu13Ni6In shows a phase transition (loss of the inversion symmetry) along with an ordering of Lu1. The structure was refined from 90 K single‐crystal X‐ray diffractometer data for an inversion twin: R3m, a = 918.97(4), c = 1820.27(7) pm, wR2 = 0.0890, 1288 F2 values, 56 variables. The low‐temperature Lu13Ni6In structure can be described as a condensation of In@Lu12 icosahedra, Ni2@Lu6 trigonal prisms, and Ni@Lu4 tetrahedra to layers that are stacked in ABC sequence. The driving force for superstructure formation is a strengthening of Lu–Ni bonding. Temperature dependent magnetic susceptibility measurements show Pauli paramagnetic behavior. [ABSTRACT FROM AUTHOR]

The equiatomic intermetallic phases CaAgIn [a = 482.75(7), b = 750.0(1), c = 835.5(1) pm], SrAgIn [a = 495.86(5), b = 794.71(9), c = 851.89(9) pm], LaAgIn [a = 489.99(5), b = 767.93(9), c = 837.53(9) pm], and EuAgIn [a = 493.02(7), b = 781.6(1), c = 844.2(1) pm] were synthesized from the elements in sealed niobum containers. They crystallize with the EuAuGe type structure, space group Imm2. The four structures were refined from single-crystal Xray data. The silver and indium atoms build up orthorhombically dis torted, puckered Ag3In3 hexagons, which are stacked in AA' sequence, leading to direct Ag-Ag and In--In interlayer bonding (e.g. 303 and 304 pm in CaAgIn). Temperature dependent magnetic susceptibility measurements show a magnetic moment of 7.40(1) μB per europium atom. EuAgIn orders antiferromagnetically at 5.7(5) K. The divalent nature of europium is also evident from 151Eu Mössbauer spectra: δ = -10.50(1) mm·s-1 at 78 K. [ABSTRACT FROM AUTHOR]

The quaternary germanides RE3 TRh4Ge4 ( RE = Ce, Pr, Nd; T = Nb, Ta) were synthesized from the elements by arc-melting and subsequent annealing in a muffle furnace. The structure of Ce3TaRh4Ge4 was refined from single-crystal X-ray diffractometer data: new type, Pbam, a = 719.9(2), b = 1495.0(3), c = 431.61(8), wR2 = 0.0678, 1004 F2 values, and 40 variables. Isotypy of the remaining phases was evident from X-ray powder patterns. Ce3TaRh4Ge4 is a new superstructure variant of the aristotype AlB2 with an ordering of cerium and tantalum on the aluminum site, whereas the honey-comb network is built up by a 1:1 ordering of rhodium and germanium. This crystal-chemical relationship is discussed based on a group-subgroup scheme. The distinctly different size of tantalum and cerium leads to a pronounced puckering of the [Rh4Ge4] network, which shows the shortest interatomic distances (253-271 pm Rh-Ge) within the Ce3TaRh4Ge4 structure. Another remarkable structural feature concerns the tantalum coordination with six shorter Ta-Rh bonds (265-266 pm) and six longer Ta-Ge bonds (294-295 pm). The [Rh4Ge4] network fully separates the tantalum and cerium atoms (Ce-Ce > 387 pm, Ta-Ta > 431 pm, and Ce-Ta > 359 pm). The electronic density of states DOS from DFT calculations show metallic behavior with large contributions of localized Ce 4f as well as itinerant ones from all constituents at the Fermi level but no significant magnetic polarization on Ce could be identified. The bonding characteristics described based on overlap populations illustrate further the crystal chemistry observations of the different coordination of Ce1 and Ce2 in Ce3TaRh4Ge4. The Rh-Ge interactions within the network are highlighted as dominant. The bonding magnitudes follow the interatomic distances and identify differences of Ta bonding vs. Ce1/Ce2 bonding with the Rh and Ge substructures. [ABSTRACT FROM AUTHOR]

The quaternary germanides RE3 TRh4Ge4 ( RE = Ce, Pr, Nd; T = Nb, Ta) were synthesized from the elements by arc-melting and subsequent annealing in a muffle furnace. The structure of Ce3TaRh4Ge4 was refined from single-crystal X-ray diffractometer data: new type, Pbam, a = 719.9(2), b = 1495.0(3), c = 431.61(8), wR2 = 0.0678, 1004 F2 values, and 40 variables. Isotypy of the remaining phases was evident from X-ray powder patterns. Ce3TaRh4Ge4 is a new superstructure variant of the aristotype AlB2 with an ordering of cerium and tantalum on the aluminum site, whereas the honey-comb network is built up by a 1:1 ordering of rhodium and germanium. This crystal-chemical relationship is discussed based on a group-subgroup scheme. The distinctly different size of tantalum and cerium leads to a pronounced puckering of the [Rh4Ge4] network, which shows the shortest interatomic distances (253-271 pm Rh-Ge) within the Ce3TaRh4Ge4 structure. Another remarkable structural feature concerns the tantalum coordination with six shorter Ta-Rh bonds (265-266 pm) and six longer Ta-Ge bonds (294-295 pm). The [Rh4Ge4] network fully separates the tantalum and cerium atoms (Ce-Ce > 387 pm, Ta-Ta > 431 pm, and Ce-Ta > 359 pm). The electronic density of states DOS from DFT calculations show metallic behavior with large contributions of localized Ce 4f as well as itinerant ones from all constituents at the Fermi level but no significant magnetic polarization on Ce could be identified. The bonding characteristics described based on overlap populations illustrate further the crystal chemistry observations of the different coordination of Ce1 and Ce2 in Ce3TaRh4Ge4. The Rh-Ge interactions within the network are highlighted as dominant. The bonding magnitudes follow the interatomic distances and identify differences of Ta bonding vs. Ce1/Ce2 bonding with the Rh and Ge substructures. [ABSTRACT FROM AUTHOR]

The gold-rich intermetallic phase Ca4Au10Zn3 was synthesized from the elements by high-frequency melting in sealed tantalum ampoules. Analyses of the sample by X-ray powder and single crystal diffraction indicated a new structure type with a small homogeneity range resulting from Au/Zn mixing: C2/ c, a = 1598.4(2), b = 819.7(1), c = 1188.2(2) pm, β = 120.93(1)°, wR2 = 0.0397, 2292 F2 values, 83 variables for Ca4Au9.66(1)Zn3.34(1), and a = 1596.6(2), b = 818.8(2), c = 1187.1(2) pm, β = 120.91(2)°, wR2 = 0.0280, 2296 F2 values, 83 variables for Ca4Au9.98(1)Zn3.02(1). The gold atoms built up a three-dimensional distorted tetrahedral network with Au-Au distances ranging from 274-294 pm. The cavities within this network are filled by calcium atoms and Zn3 triangles (272-279 pm Zn-Zn) in an ordered manner. The small homogeneity range Ca4Au10- xZn3+ x concerns Au/Zn mixing within the triangles and the tetrahedral network as well. The crystal chemical relationship with the aristotype AlB2 is discussed on the basis of a group-subgroup scheme. [ABSTRACT FROM AUTHOR]

The gallides SrRh2Ga2, SrIr2Ga2, and Sr3Rh4Ga4 were obtained from the elements by induction melting and subsequent annealing. They were investigated by powder and single-crystal X-ray diffraction: CaRh2B2 type, Fddd, a = 573.2(1), b = 1051.3(1), c = 1343.7(2) pm, wR2 = 0.0218, 398 F2 values, 15 variables for SrRh2Ga2; a = 576.0(1), b = 1045.5(1), c = 1350.6(3) pm for SrIr2Ga2, and Na3Pt4Ge4 type, I $\bar{4}$3 m, a = 777.4(2) pm, wR2 = 0.0234, 190 F2 values, 11 variables for Sr3Ir4Ga4. The gallides SrRh2Ga2 and Sr3Ir4Ga4 exhibit complex, covalently bonded three-dimensional [Rh2Ga2] and [Ir4Ga4] networks with short Rh-Ga (241-246 pm) and Ir-Ga (243-259 pm) distances. The strontium atoms fill large cages within these networks. They are coordinated by 8 Rh + 10 Ga in SrRh2Ga2 and by 4 Ir + 8 Ga in Sr3Ir4Ga4. The structure of SrRh2Ga2 is discussed along with the monoclinic distortion variants HoNi2B2 and BaPt2Ga2 on the basis of a group-subgroup scheme. [ABSTRACT FROM AUTHOR]

The gallide LaRh3Ga2 was obtained by arc-melting of the elements and subsequent annealing of the product button in a high-frequency furnace. The sample was studied by powder X-ray diffraction and the structure was refined from single crystal data of a trilling: ErRh3Si2 type (CaCu5 superstructure), Imma, a = 760.1(2), b = 975.6(3), c = 564.0(2) pm, wR = 0.0358 for 717 F2 values and 23 variables; domain ratio 0.36(1) / 0.28(1) / 0.35(1). The rhodium atoms build up Kagomé networks (281.8 and 282.2 pm Rh-Rh), which are condensed through the gallium atoms (249.6-251.0 pm Rh-Ga). The lanthanum atoms fill large voids left by the three-dimensional [Rh3Ga2] network. They have coordination number 18 (6 Ga + 12 Rh) in form of a hexa-capped hexagonal prism. The crystal chemical relationship with the aristotype CaCu5 is briefly discussed on the basis of a group-subgroup scheme. [ABSTRACT FROM AUTHOR]

The intermetallic zinc compounds AAu4Zn2 ( A = Ca, Ce, Pr, Nd) were obtained by induction melting of the elements in sealed tantalum tubes. The samples were studied by X-ray diffraction on powders. The structures of the calcium and the cerium compound were refined from single crystal diffraction data: YbAl4Mo2 type, I4/ mmm, a = 692.8(1), c = 527.6(1) pm, wR2 = 0.0304, 244 F2 values and 11 variables for CaAu4.08Zn1.92 and a = 699.6(1), c = 531.2(1) pm, wR2 = 0.1152, 186 F2 values and 10 variables for CeAu4Zn2. The 4 d site of the calcium compound shows small mixed Zn/Au occupancy. The AAu4Zn2 structures consist of three-dimensional gold networks (272-286 pm Au-Au in CeAu4Zn2), which are penetrated by linear infinite zinc chains (266 pm Zn-Zn in CeAu4Zn2) that extend along the c axis. The calcium or rare earth atoms fill Au12 cavities within the networks. Temperature dependent magnetic susceptibility measurements reveal Pauli paramagnetism for CaAu4Zn2 and Curie-Weiss paramagnetism for the cerium, praseodymium, and neodymium compound, respectively. No magnetic ordering was evident down to 2.5 K. The static intermediate-valent compound Ce2RuZn4 crystallizes with a superstructure of CeAu4Zn2 ( klassengleiche subgroup P4/ nmm) with a different but fully ordered substitution on the transition metal sites. This structural relationship is discussed on the basis of a group-subgroup scheme. [ABSTRACT FROM AUTHOR]

The intermetallic compounds Sr2Au6.52Zn2.48, Sr2Au6Zn3, and Sr2Au6Ga3 were obtained by induction melting of the elements in sealed tantalum tubes. Their structures were studied by X-ray diffraction on powders and refined from single crystal diffraction data: R $\bar{3}$ c, a = 844.5(2), c = 2187.7(5) pm, wR2 = 0.0411, 936 F2 values and 20 variables for Sr2Au6.52Zn2.48; a = 841.6(2), c = 2191.5(7) pm, wR2 = 0.0126, 587 F2 values and 19 variables for Sr2Au6Zn3; and a = 841.9(2), c = 2191.1(7) pm, wR2 = 0.0199, 660 F2 values and 19 variables for Sr2Au6Ga3. The gold substructures of Sr2Au6Zn3 and Sr2Au6Ga3 can be considered as diamond polytypes with 6R stacking sequences (287-304 pm Au-Au in Sr2Au6Zn3). The cavities formed by this network are filled in an ordered manner by strontium atoms and Zn3 (281 pm Zn-Zn), respectively Ga3 (286 pm Ga-Ga) triangles in a 2:1 ratio. Consequently one can describe the Sr2Au6Zn3 and Sr2Au6Ga3 structures as ordered substitution variants of the Zintl phase CaIn2. This structural relationship is discussed on the basis of a group-subgroup Scheme. Sr2Au6.52Zn2.48 shows Zn/Au mixing on the triangle. [ABSTRACT FROM AUTHOR]

The intermetallic compounds Sr2Au6.52Zn2.48, Sr2Au6Zn3, and Sr2Au6Ga3 were obtained by induction melting of the elements in sealed tantalum tubes. Their structures were studied by X-ray diffraction on powders and refined from single crystal diffraction data: R $\bar{3}$ c, a = 844.5(2), c = 2187.7(5) pm, wR2 = 0.0411, 936 F2 values and 20 variables for Sr2Au6.52Zn2.48; a = 841.6(2), c = 2191.5(7) pm, wR2 = 0.0126, 587 F2 values and 19 variables for Sr2Au6Zn3; and a = 841.9(2), c = 2191.1(7) pm, wR2 = 0.0199, 660 F2 values and 19 variables for Sr2Au6Ga3. The gold substructures of Sr2Au6Zn3 and Sr2Au6Ga3 can be considered as diamond polytypes with 6R stacking sequences (287-304 pm Au-Au in Sr2Au6Zn3). The cavities formed by this network are filled in an ordered manner by strontium atoms and Zn3 (281 pm Zn-Zn), respectively Ga3 (286 pm Ga-Ga) triangles in a 2:1 ratio. Consequently one can describe the Sr2Au6Zn3 and Sr2Au6Ga3 structures as ordered substitution variants of the Zintl phase CaIn2. This structural relationship is discussed on the basis of a group-subgroup Scheme. Sr2Au6.52Zn2.48 shows Zn/Au mixing on the triangle. [ABSTRACT FROM AUTHOR]

The intermetallic compounds ScPdZn and ScPtZn were prepared from the elements by high-frequency melting in sealed tantalum ampoules. Both structures were refined from single crystal X-ray diffractometer data: YAlGe type, Cmcm, a = 429.53(8), b = 907.7(1), c = 527.86(1) pm, wR2 = 0.0375, 231 F2 values, for ScPdZn and a = 425.3(1), b = 918.4(2), c = 523.3(1) pm, wR2 = 0.0399, 213 F2 values for ScPtZn with 14 variables per refinement. The structures are orthorhombically distorted variants of the AlB2 type. The scandium and palladium (platinum atoms) build up ordered networks Sc3Pd3 and Sc3Pt3 (boron networks) which are slightly shifted with respect to each other. These networks are penetrated by chains of zinc atoms (262 pm in ScPtZn) which correspond to the aluminum positions, i.e. Zn(ScPd) and Zn(ScPt). The corresponding group-subgroup scheme and the differences in chemical bonding with respect to other AlB2-derived REPdZn and REPtZn compounds are discussed. 45Sc solid state NMR spectra confirm the single crystallographic scandium sites. From electronic band structure calculations the two compounds are found metallic with free electron like behavior at the Fermi level. A larger cohesive energy for ScPtZn suggests a more strongly bonded intermetallic than ScPdZn. Electron localization and overlap population analyses identify the largest bonding for scandium with the transition metal (Pd, Pt). [ABSTRACT FROM AUTHOR]

Studies the crystal structure of rare earth ruthenium carbides. Superstructures of erbium ruthenium carbide; Link between ruthenium-carbon layers and single carbon atoms and carbon pairs; Chemical bonding.

High quality single crystals of Ce3Pt4Ge6 are obtained by repeated arc melting of the elements under Ar and subsequent annealing just below the melting point (2 h; slow cooling to 25 °C). [ABSTRACT FROM AUTHOR]

The title compounds are prepared from the elements by arc-melting and subsequent annealing (1400 K, 14 d). [ABSTRACT FROM AUTHOR]

Crystals of the title phosphide are prepared by reaction of the elements in a Pb flux (620 K for 1 d and 1070 K for 1 d). [ABSTRACT FROM AUTHOR]

The title compound is prepared by induction melting of the elements (Ta tube, Ar flow, 1300 K, 10 min) followed by annealing at 770 K (1 d). [ABSTRACT FROM AUTHOR]

Sr2Au6.52Zn2.48 (I), Sr2Au6Zn3 (II), and Sr2Au6Ga3 (III) intermetallic compounds are obtained by induction melting of the elements in sealed Ta tubes (1. [ABSTRACT FROM AUTHOR]