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The plumbide EuPdPb was synthesized in polycrystalline form by reaction of the elements in a sealed niobium ampoule in a muffle furnace. The structure was refined from single-crystal X-ray diffractometer data: TiNiSi type, Pnma, a=752.4(2), b=476.0(2), c=826.8(2) pm, wR2=0.0485, 704 F 2 values and 20 variables. The europium atoms are coordinated by two tilted and puckered Pd3Pb3 hexagons (280–289 pm Pd–Pb) with pronounced Eu–Pd bonding (312–339 pm). Temperature-dependent magnetic susceptibility measurements show Curie-Weiss behaviour and an experimental magnetic moment of 7.35(1) μB per Eu atom. EuPdPb orders antiferromagnetically at T N=13.8(5) K and shows a metamagnetic transition at a critical field of 15 kOe. 151Eu Mössbauer spectra confirm divalent europium (δ=–10.04(1) mm s−1) and show full magnetic hyperfine field splitting (B hf=21.1(1) T) at 6 K.

Polycrystalline samples of Sr 0.95 Eu 0.05 Ba 8 [BN 2 ] 6 and Eu 0.937 Ba 8 [BN 2 ] 6 were synthesized via conventional solid-state reaction from the binary precursor compounds Sr 3 N 2 , EuN, Ba 3 N 2 and BN at 1000 °C. The structure of Eu 0.937 Ba 8 [BN 2 ] 6 was refined from single crystal X-ray diffractometer data: Eu 0.937 Ba 8 [BN 2 ] 6 type, Fd 3 ¯ m, a = 1594.54(9) pm, w R 2 = 0.0654, 380 F 2 values and 23 variables. The 8 a europium site shows an occupancy of only 93.7(9) % suggesting partial oxidation of europium to fulfil an electron-precise description, i. e. Eu II 0.81 Eu III 0.13 Ba 8 [BN 2 ] 6 . The mixed europium valence was confirmed by magnetic susceptibility measurements (reduced magnetic moment of 7.28 μ B per europium atom) and 151 Eu Mossbauer spectroscopy (Eu II : Eu III = 82: 18). The nitridoborate anions are coordinated by slightly distorted, mono-capped (europium) square prisms formed by the barium atoms. All metal cations are hexa-coordinated by nitrogen atoms. The EPR spectra of Eu x Sr 1-x Ba 8 [BN 2 ] 6 samples (0.001 ≤ x ≤ 0.01) suggest close to cubic local symmetry of the Eu 2+ dopant ions and reveal some highly unusual features: Magnetic hyperfine splitting is only observed with one of the Eu nuclear isotopes, and the coupling constant of 243.6 MHz is extremely large compared to values (90–100 MHz) typically observed in the literature for Eu 2+ doped crystalline materials.

Pyrochlore-type Eu2Ta2(O,N)7+δ phases were prepared by reaction of ammonia with an amorphous europium tantalum oxide precursor. 151Eu Mossbauer and EPR spectroscopy as well as magnetic susceptibility measurements point to the presence of exclusively Eu3+. For phase-pure samples (X-ray powder diffraction), the nitrogen content varies between 1.0 and 1.8 wt %, leading to compositions in the range Eu2Ta2O7.1N0.6 – Eu2Ta2O6.5N1.0. Pyrochlore-type phases are structurally derived from the fluorite type with 1/8 of the anions missing, resulting in an ideal composition A2B2X7. In Eu2Ta2(O,N)7+δ the excess anions partly occupy these vacancies. The prepared phases are colorless with a direct optical bandgap of 4.3 eV and they show the typical Van Vleck paramagnetic behavior known for trivalent Eu atoms.

The ternary antimonide YIrSb was synthesized from the binary precursor YIr and elemental antimony by a diffusion controlled solid-state reaction. Single crystals were obtained by a flux technique with elemental bismuth as an inert solvent. The YIrSb structure (TiNiSi type, space group Pnma) was refined from single-crystal X-ray diffractometer data: a = 711.06(9), b = 447.74(5), c = 784.20(8) pm, wR2 = 0.0455, 535 F2 values, 20 variables. 89Y solid state MAS NMR and 121Sb Mossbauer spectra show single resonance lines in agreement with single-crystal X-ray data. YIrSb is a Pauli paramagnet.

The reaction of the metalloid tin cluster [Sn10(Hyp)4]2−with (Ph3P)Au-SHyp (Hyp = Si(SiMe3)3) gave an intermetalloid cluster [Au3Sn18(Hyp)8]−1, which is the longest intermetalloid chain compound of tin to date.

Eu5Al2Sb6 was synthesized from the elements in niobium ampoules. It crystallizes in the orthorhombic crystal system (a = 1027.55(7), b = 1200.28(6), c = 1324.22(7) pm) with space group Pnma (no. 62), isostructural to Sr5Al2Sb6, and can be described as a Zintl phase. The Al atoms are tetrahedrally surrounded by Sb atoms, forming branched strands. Besides Sb3− anions, antimony Sb24− dumbbells can also be found in the crystal structure. Eu5Al2Sb6 [≡(Eu2+)5(Al3+)2(Sb3−)4(Sb24−)] exhibits three magnetic ordering phenomena at T1 = 12.3(1), T2 = 10.6(1) and T3 = 3.0(1) K, obtained by heat capacity measurements. While T3 is of antiferromagnetic nature, T1 and T2 correspond to canted antiferromagnetic transitions. Resistivity investigations indicate that the title compound is a semiconductor, in line with the band structure calculations. Spin exchange parameters, calculated using mapping analysis, confirm that the magnetic phase transition at TN = 3.5(1) is associated with the ordering of Eu1 atoms. The divalent character has been confirmed by 151Eu Mossbauer spectroscopic studies. Measurements conducted at 5 K show a hyperfine field splitting for two of the three Eu sites, underlining the magnetic data. Additionally, 121Sb Mossbauer spectroscopic studies have been conducted on Eu5Al2Sb6 and isostructural Sr5Al2Sb6.

The reaction of the antimony(i) compound ArSb (1) (where Ar = C

Four new MPtAl

The rare earth borosulfates RE2[B2(SO4)6] with RE = Y, La-Nd, Sm, Eu and Tb-Lu were synthesised under solvothermal conditions starting from the metal chlorides (Pr, Nd, Eu), the metal oxides (Y, La, Ce, Sm, Tb, Dy, Er, Tm, Lu), or the metal powders (Ho, Yb). They crystallize isotypically with Gd2[B2(SO4)6] in space group C2/c (Z = 4, a = 1346.9(3)-1379.24(17) pm, b = 1136.4(3)-1158.87(14) pm, c = 1079.9(3)-1139.54(14) pm, β = 93.369(8)-93.611(4)°). The anionic structure consists of an open-branched vierer single ring {oB, 1r}[B2S2O12(SO3)4]6-, similar to the mineral eakerite (Ca2Al2Sn[Si6O18](OH)2·2H2O) which contains {oB, 1r}[Si4O12(SiO3)2]12- moieties. The fluorescence spectroscopy of the samples with RE = Ce, Eu and Tb features emissions in the deep UV, the red, and the green part of the spectrum and furthermore revealed a weak coordination behaviour of the borosulfate anion. Thermal analysis of Eu2[B2(SO4)6] showed the highest thermal stability observed for borosulfates so far; respective trends within the borosulfate family are discussed. Additionally, the compounds were characterised by magnetic measurements, vibrational and 151Eu Mößbauer spectroscopy.

The rare earth borosulfates RE2[B2(SO4)6] with RE = Y, La–Nd, Sm, Eu and Tb–Lu were synthesised under solvothermal conditions starting from the metal chlorides (Pr, Nd, Eu), the metal oxides (Y, La, Ce, Sm, Tb, Dy, Er, Tm, Lu), or the metal powders (Ho, Yb). They crystallize isotypically with Gd2[B2(SO4)6] in space group C2/c (Z = 4, a = 1346.9(3)–1379.24(17) pm, b = 1136.4(3)–1158.87(14) pm, c = 1079.9(3)–1139.54(14) pm, β = 93.369(8)–93.611(4)°). The anionic structure consists of an open-branched vierer single ring {oB, 1r}[B2S2O12(SO3)4]6−, similar to the mineral eakerite (Ca2Al2Sn[Si6O18](OH)2·2H2O) which contains {oB, 1r}[Si4O12(SiO3)2]12− moieties. The fluorescence spectroscopy of the samples with RE = Ce, Eu and Tb features emissions in the deep UV, the red, and the green part of the spectrum and furthermore revealed a weak coordination behaviour of the borosulfate anion. Thermal analysis of Eu2[B2(SO4)6] showed the highest thermal stability observed for borosulfates so far; respective trends within the borosulfate family are discussed. Additionally, the compounds were characterised by magnetic measurements, vibrational and 151Eu Mosbauer spectroscopy.

Eu

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 intermetallic compound EuAu3Al2 has been prepared by reaction of the elements in tantalum ampules. The structure was refined from single-crystal data, indicating that the title compound crystallizes in the orthorhombic crystal system (a = 1310.36(4), b = 547.87(1), c = 681.26(2) pm) with space group Pnma (wR2 = 0.0266, 1038 F(2) values, 35 parameters) and is isostructural to SrAu3Al2 (LT-SrZn5 type). Full ordering of the gold and aluminum atoms was observed. Theoretical calculations confirm that the title compound can be described as a polar intermetallic phase containing a polyanionic [Au3Al2](δ-) network featuring interconnected strands of edge-sharing [AlAu4] tetrahedra. Magnetic measurements and (151)Eu Mössbauer spectroscopic investigations confirmed the divalent character of the europium atoms. Ferromagnetic ordering below TC = 16.5(1) K was observed. Heat capacity measurements showed a λ-type anomaly at T = 15.7(1) K, in line with the ordering temperature from the susceptibility measurements. The magnetocaloric properties of EuAu3Al2 were determined, and a magnetic entropy of ΔSM = -4.8 J kg(-1) K(-1) for a field change of 0 to 50 kOe was determined. Band structure calculations found that the f-bands of Eu present at the Fermi level of non-spin-polarized calculations are responsible for the ferromagnetic ordering in this phase, whereas COHP chemical bonding coupled with Bader charge analysis confirmed the description of the structure as covalently bonded polyanionic [Au3Al2](δ-) network interacting ionically with Eu(δ+).

Fourteen X-ray-pure intermetallic compounds RE 10 TCd3 (RE = Ho, Er, Tm, Lu; T = Fe, Co, Ni, Ru) and Y10FeCd3 were obtained through high-frequency melting of the elements in sealed niobium tubes and subsequent annealing in a muffle furnace. They adopt the Er10FeCd3 structure, a ternary ordered version of the Co2Al5 type. Temperature-dependent magnetic susceptibility measurements show Pauli paramagnetism for the lutetium compounds Lu10FeCd3, Lu10CoCd3, and Lu10RuCd3. The RE 10 TCd3 phases with holmium, erbium, and thulium show Curie–Weiss paramagnetism and the experimental magnetic moments match with the free ion values of RE 3+. All these compounds order antiferromagnetically. The highest Néel temperature was observed for the holmium compounds, e.g. 46.5 K for Ho10RuCd3. Some of the RE 10 TCd3 phases show field-induced spin reorientations. A 57Fe Mössbauer spectrum of Y10FeCd3 confirms the single crystallographic iron site.

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.

3d transition metal nitridophosphates M

The most fruitful synthetic route to metalloid tin clusters applies the disproportionation reaction of metastable Sn(I) halide solutions, whereby Si(SiMe3)3 is mostly used as the stabilizing substituent. Here, we describe the synthesis and application of the slightly modified substituent Ge(SiMe3)3, which can be used for the synthesis of metalloid tin clusters to give the neutral cluster Sn10[Ge(SiMe3)3]6 as well as the charged clusters {Sn10[Ge(SiMe3)3]5}− and {Sn10[Ge(SiMe3)3]4}2−. The obtained metalloid clusters are structurally similar to their Si(SiMe3)3 derivatives. However, differences with respect to the stability in solution are observed. Additionally, a different electronic situation for the tin atoms is realized as shown by 119mSn Mössbauer spectroscopy, giving further insight into the different kinds of tin atoms within the metalloid cluster {Sn10[Ge(SiMe3)3]4}2−. The synthesis of diverse derivatives gives the opportunity to check the influence of the substituent for further investigations of metalloid tin cluster compounds.

Highly condensed nitridosilicates doped with Eu

Recently, we reported the synthesis and investigations of EuSr

Reactions of the organotin selenide chloride clusters [(R1 SnIV )3 Se4 Cl] (A, R1 =CMe2 CH2 C(O)Me) or [(R1 SnIV )4 Se6 ] (B) with [Cu(PPh3 )3-x Clx ] yield cluster compounds with different inorganic, mixed-valence core structures: [Cu4 SnII SnIV6 Se12 ], [Cu2 SnII2 SnIV4 Se8 Cl2 ], [Cu2 SnII SnIV4 Se8 ], [Cu2 SnII2 SnIV2 Se4 Cl4 ], and [Cu2 SnIV2 Se4 ]. Five of the compounds, namely [(CuPPh3 )2 {(R1 SnIV )2 Se4 }] (1), [(CuPPh3 )2 SnII {(R2 SnIV )2 Se4 }2 ] (2), [(CuPPh3 )2 (SnII Cl)2 {(RSnIV )2 Se4 }2 ] (3) [(CuPPh3 )2 (SnII Cu2 ){(R1 SnIV )2 Se4 }3 ] (4), and [Cu(CuPPh3 )(SnII Cu2 ){(R1 SnIV )2 Se4 }3 ] (5) are structurally closely related. They are based on [(CuPPh3 )2 {(RSnIV )2 Se4 }n ] aggregates comprising [(RSnIV )2 Se4 ] and [CuPPh3 ] building units, which are linked by further metal atoms. A sixth compound, [(CuPPh3 )2 (SnII Cl)2 {(R1 SnIV Cl)Se2 }2 ] (6), differs from the others by containing [(RSnIV Cl)Se2 ] units instead, which affects the absorption properties. The compounds were analyzed by single-crystal X-ray diffraction, NMR and 119 Sn Mossbauer spectroscopy, DFT calculations as well as optical absorption experiments.

The intermetallic gold compounds RE 4Mg3Au10 (RE = La, Ce, Pr) and RE 4Cd3Au10 (RE = Y, La–Nd, Sm, Gd–Dy) were obtained from the elements through high-frequency melting in sealed niobium tubes and subsequent annealing in a muffle furnace. The new aurides crystallize with the Ca4In3Au10-type structure. They were characterized through Guinier powder patterns. The structures of Pr4.46Cd2.54Au10 and Tb4.38Cd2.62Au10 were refined from single crystal X-ray diffractometer data: Cmce, a = 1396.73(6), b = 1009.38(3), c = 1019.51(3) pm, wR2 = 0.0423, 1281 F 2 values, 47 variables for Pr4.46Cd2.54Au10 and a = 1362.68(3), b = 995.52(4), c = 1003.79(3) pm, wR2 = 0.0381, 1594 F 2 values, F 2 47 variables for Tb4.38Cd2.62Au10. The 8e sites of both crystals show substantial Cd/Pr respectively Cd/Tb mixing, indicating small homogeneity ranges for all RE 4+x Mg3–x Au10 and RE 4+x Cd3–x Au10 aurides. The gold atoms in these aurides form a pronounced two-dimensional substructure (275–327 pm Au–Au in Pr4.46Cd2.54Au10) which encages the Mg1/Cd1 (coordination number 8) and RE2 (coordination number 11) atoms. These blocks are separated by the Mg2/Cd2 and RE1 atoms with an intergrowth of Mg2/Cd2@Au8 and RE1@Au10 polyhedra. Temperature dependent magnetic susceptibility and specific heat measurements of Tb4Cd3Au10 have shown antiferromagnetic ordering at a Néel temperature of 12(1) K.

The ternary aurides RE 4Mg3Au10 (RE=Y, Nd, Sm, Gd–Dy) and their silver analogues were synthesized by induction melting of the elements in sealed niobium tubes. These intermetallic phases were characterized by powder X-ray diffraction. They crystallize with the Ca4In3Au10-type structure, which, from a geometrical point of view, is a ternary ordered version of Zr7Ni10 with the rare earth and magnesium atoms ordering on the four crystallographically independent zirconium sites. The structures of crystals from three differently prepared gadolinium samples were refined from single-crystal X-ray diffractometer data: Cmca, a=1366.69(3), b=998.07(4), c=1005.54(3) pm, wR2=0.0332, 1234 F 2 values, 46 variables for Gd4.43Mg2.57Au10, a=1378.7(1), b=1005.3(1), c=1011.2(1) pm, wR2=0.0409, 1255 F 2 values, 48 variables for Gd5.50Mg1.50Au10, and a=1350.2(5), b=995.5(1), c=1009.3(1) pm, wR2=0.0478, 1075 F 2 values, 48 variables for Gd5.61Mg1.39Au10. All crystals show substantial Mg/Gd mixing on two sites. The gold atoms form a pronounced two-dimensional substructure with Au–Au distances of 278 to 297 pm in Gd4.43Mg2.57Au10. These gold blocks are condensed via magnesium atoms (278–315 pm Mg–Au). The gadolinium atoms fill larger cavities within the three-dimensional networks. The magnesium vs. gadolinium site preference is a consequence of the different coordination numbers of the cation sites. All phases show homogeneity ranges RE 4+x Mg3–x Ag10 and RE 4+x Mg3–x Au10. The influence of the synthesis conditions is briefly discussed.

The rare earth-rich intermetallic cadmium compounds RE10TCd3 (RE = Y, Tb – Tm, Lu; T = Fe, Co, Ni, Ru, Rh, Pd) were synthesized by induction melting of the elements in sealed niobium ampoules. These cadmium intermetallics crystallize with an ordered variant of the hexagonal Co2Al5 type, space group P63/mmc. The three crystallographically independent rare earth atoms lie on the aluminum sites, while the transition metal and cadmium atoms are ordered on the two cobalt positions. The structures of Y10Co1.103Cd2.897, Y10NiCd3, Y10RuCd3, Y10PdCd3, Er9.92FeCd3.08, and Er9.82NiCd3.18 were refined from single-crystal X-ray diffraction data. Some of the crystals showed small degrees of RE/Cd, respectively T/Cd mixing. The striking structural building units are transition metal centered T@RE6 trigonal prisms (TP) that are condensed to empty RE6 octahedra (O), building infinite …TP–O–O… rows in c direction. The second motifs are slightly flattened RE3@Cd6RE16 icosahedra. The latter are condensed via common triangular faced along the c axis. Each …TP–O–O… row is enrolled by three rows of condensed RE3@Cd6RE16 icosahedra in the motif of a hexagonal rod packing.

The reaction of the metalloid tin cluster [Sn

We have synthesized two new Eu-based compounds, EuSr

We have synthesized two new Eu-based compounds, EuSr2Bi2S4F4 and Eu2SrBi2S4F4 which are derivatives of Eu3Bi2S4F4, an intrinsic superconductor with Tc = 1.5 K. They belong to a tetragonal structure (SG: I4/mmm, Z = 2), similar to the parent compound Eu3Bi2S4F4. Our structural and 151Eu M\"ossbauer spectroscopy studies show that in EuSr2Bi2S4F4, Eu-atoms exclusively occupy the crystallographic 2a-sites. In Eu2SrBi2S4F4, 2a-sites are fully occupied by Eu-atoms and the other half of Eu-atoms and Sr-atoms together fully occupy 4e-sites in a statistical distribution. In both compounds Eu atoms occupying the crystallographic 2a-sites are in a homogeneous mixed valent state ~ 2.6 - 2.7. From our magnetization studies in an applied H = 9 Tesla, we infer that the valence of Eu-atoms in Eu2SrBi2S4F4 at the 2a-sites exhibits a shift towards 2+. Our XPS studies corroborate the occurrence of valence fluctuations of Eu and after Ar-ion sputtering show evidence of enhanced population of Eu2+-states. Resistivity measurements, down to 2 K suggest a semi-metallic nature for both compounds.

The synthesis of zero-valent iron (Fe(0)) nanoparticles in pyridine using lithium bipyridinyl ([LiBipy]) or lithium pyridinyl ([LiPy]) is presented. FeCl3 is used as the most simple starting material and reduced either in a [LiBipy]-driven two-step approach or in a [LiPy]-driven one-pot synthesis. High-quality nanoparticles are obtained with uniform, spherical shape, and mean diameters of 2.9 ± 0.5 nm ([LiBipy]) or 4.1 ± 0.7 nm ([LiPy]). The as-prepared, high purity Fe(0) nanoparticles are monocrystalline. In addition to particle characterization (high-resolution transmission electron microscopy, scanning transmission electron microscopy, dynamic light scattering), composition and purity are examined in detail based on electron diffraction, X-ray powder diffraction, elemental analysis, infrared spectroscopy, 57 Fe Mossbauer spectroscopy, and magnetic measurements. Due to their small size and high purity, the Fe(0) nanoparticles are highly reactive. They can be used in follow-up reactions to obtain a variety of iron compounds, which is exemplarily shown for the transformation to iron carbide (Fe3 C) nanoparticles, the reaction with sulfur to obtain FeS nanoparticles, or the direct reaction with pentamethylcyclopentadiene to FeCp*2 (Cp*: pentamethylcyclopentadienyl).

The intermetallic compound EuAu3Al2 has been prepared by reaction of the elements in tantalum ampules. The structure was refined from single-crystal data, indicating that the title compound crystallizes in the orthorhombic crystal system (a = 1310.36(4), b = 547.87(1), c = 681.26(2) pm) with space group Pnma (wR2 = 0.0266, 1038 F(2) values, 35 parameters) and is isostructural to SrAu3Al2 (LT-SrZn5 type). Full ordering of the gold and aluminum atoms was observed. Theoretical calculations confirm that the title compound can be described as a polar intermetallic phase containing a polyanionic [Au3Al2](δ-) network featuring interconnected strands of edge-sharing [AlAu4] tetrahedra. Magnetic measurements and (151)Eu Mossbauer spectroscopic investigations confirmed the divalent character of the europium atoms. Ferromagnetic ordering below TC = 16.5(1) K was observed. Heat capacity measurements showed a λ-type anomaly at T = 15.7(1) K, in line with the ordering temperature from the susceptibility measurements. The magnetocaloric properties of EuAu3Al2 were determined, and a magnetic entropy of ΔSM = -4.8 J kg(-1) K(-1) for a field change of 0 to 50 kOe was determined. Band structure calculations found that the f-bands of Eu present at the Fermi level of non-spin-polarized calculations are responsible for the ferromagnetic ordering in this phase, whereas COHP chemical bonding coupled with Bader charge analysis confirmed the description of the structure as covalently bonded polyanionic [Au3Al2](δ-) network interacting ionically with Eu(δ+).

The title compounds are prepared by induction melting of the elements in sealed Nb tubes (rapidly heating to about 1500 K, 1300 K for 30 min, and 900 K for 2 h).

The title compounds are synthesized from the elements (flowing Ar, 1500 K for 2 min, 1300 K for 45 min, and 900 K for 2 h) and characterized by powder XRD.

FTCH is a recently developed material which consists of a collagen fleece containing fibrinogen, thrombin, and aprotinin integrated into its surface. FTCH is highly effective in sealing of tissues and in establishing hemostasis. We evaluated FTCH in experimentally produced liver (n = 6) and splenic (n = 12) injuries in 18 adult mongrel dogs. The stability of the parenchymal seal of the splenic injuries was tested by splenic tissue pressure elevation after temporary ligation of the splenic vein. No breakthrough bleeding occurred up to a parenchymal pressure of 16.3 +/- 5 mm Hg. Complete hemostasis was easily achieved in all animals before closure. When the dogs were re-explored postoperatively at intervals of either 14 or 30 days, there was no gross evidence of recurrent bleeding. Histologic examinations demonstrated a partially regenerated capsule covering an unspecific fibrovascular granulation tissue and progressive resorption of FTCH without significant inflammatory response. We conclude the following: FTCH provides adequate hemostatic control of experimental liver and splenic injuries. FTCH has excellent tissue compatibility and can be applied easily and safely to hemorrhaging parenchymal wounds. It will not replace adequate surgical techniques, but could be useful as a quickly available and easily applicable hemostatic means in diffuse or acute bleeding of liver and spleen.