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Eu2Ni8Si3 and its anti‐type representative Sr2Pt3Al8 were synthesized from the elements. They crystallize in the tetragonal crystal system with space group P42/nmc and with lattice parameters of a=997.9(1) and c=747.6(1) pm (Eu2Ni8Si3) as well as a=1082.9(2) and c=823.3(2) pm (Sr2Pt3Al8). Both compounds were investigated via single crystal X‐ray diffraction, indicating slight Si/Ni mixing for the silicide. Sr2Pt3Al8 exhibits a temperature independent magnetic susceptibility, suggesting superimposed dia‐ and Pauli‐paramagnetic contributions. The independent Al and Pt sites of the platinide were further characterized by 27Al and 195Pt solid‐state NMR spectroscopy, which were assigned with the help of electronic structure calculations. ICOHP calculations and Bader charges were used to analyze the bonding situation. Eu2Ni8Si3 in contrast is paramagnetic with a ferromagnetic transition at TC=46.9(2) K and exhibits an effective magnetic moment of μeff=6.61(1) μB per Eu atom. The latter is in line with an intermediate valence that was further proven by 151Eu Mößbauer spectroscopic investigations. At 300 K, the refined Eu2+/Eu3+ ratios are 60 %/40 %, at 78 K 62 % and 38 % (Eu2+/Eu3+) are observed, being in line with the ratio deduced from the magnetic susceptibility. Finally, at 6 K a ratio of 68 % Eu2+ and 32 % Eu3+ was observed. Below the Curie temperature, the Eu2+ signal shows a full magnetic hyperfine splitting, with an internal magnetic field value of B0=28.4 T. [ABSTRACT FROM AUTHOR]

The CsCl/LiCl system has been studied for over a century now. Numerous phases have been predicted – only three have hitherto been found. We present the synthesis and single‐crystal structure of the cesium lithium pentachloride Cs3Li2Cl5, predicted earlier but with a different structure. The anhydrous new phase readily reacts to Cs3LiCl4·4H2O in air. The tetrahydrate can also be obtained through the simplest, most inexpensive and green synthesis possible: an immediate, room‐temperature mechanosynthesis from only CsCl and LiCl (3:1) in air. Differential scanning calorimetry (DSC) and thermogravimetric analyses (TGA), as well as in situ temperature‐dependent powder X‐ray diffraction studies on this second ever reported ternary alkali chloride hydrate allowed for a revision of the CsCl/LiCl phase diagram. Density of states and total energy calculations further elucidate the new alkali chlorides and update the relative stability of previous structure predictions. [ABSTRACT FROM AUTHOR]

Tuning of the magnetic properties of intermetallic materials is increasingly gaining interest in the chemistry community. We report on the successful synthesis and magnetic characterizations of the two new quaternary boride series MRh6- nRu nB3 (M = Co, Ni; 1 ≤ n ≤ 5). Powder samples have been synthesized by arc-melting the elements under purified argon in a water-cooled copper crucible. The products were characterized by powder X-ray diffraction through Rietveld refinements as well as EDX measurements. All phases crystallize in the hexagonal Th7Fe3 structure type (space group P63 mc, no. 186, Z = 2). In the Co-based series, the lattice parameters decrease linearly with increasing ruthenium content, whereas in the Ni-based series they remain nearly constant for the Rh-rich side then decrease with increasing Ru content. Significant ferromagnetic interactions are observed for the Co-based series, and they decrease linearly with increasing Ru content with magnetic moments decreasing from 0.74 µB (CoRh5RuB3) to 0.13 µB (CoRhRu5B3) at 5 K and 5 T. Pauli paramagnetism dominates the Ni-based series. [ABSTRACT FROM AUTHOR]

Nb2RuB2 and Ta2RuB2 phases were recently predicted by GGA-VASP structure optimization to crystallize in the Nb2OsB2-type structure. Although the Fe-based (Mo2FeB2 type) and Os-based (Nb2OsB2 type, superstructure variant of Mo2FeB2 type) analogues have been synthesized and characterized successfully, the Ru-based phases remained unknown. Crystal structure prediction of Nb2RuB2 and Ta2RuB2 phases, using an evolutionary algorithm, led to the AlMn2B2-type structure in contrast to the aforementioned optimization; however, phonon calculations showed that the Nb2OsB2-type phases are dynamically more stable than the AlMn2B2-type phases. A slightly modified synthetic strategy finally led to the successful preparation of the predicted phases. The extremely quick arc-melting procedure, under argon atmosphere, not only led to a quantitative amount of the phases but also to single crystals suitable for structure determination. Powder and single-crystal X-ray diffraction as well as EDX analysis of the metal ratio have confirmed the GGA-VASP structure optimization: Nb2RuB2 and Ta2RuB2 compounds indeed crystallize isotypically with Nb2OsB2 structure, a superstructure variant of Mo2FeB2 type, in which B-dumbbells and Peierls-distorted Ru-chains are found. Susceptibility measurements on a Ta2RuB2 single crystal reveal no superconducting transition down to 2 K, even though some features in the band structures of both phases, similar to those reported in superconducting NbRuB, hinted at possible superconductivity. [ABSTRACT FROM AUTHOR]

The new intermetallic compound Sr2Pd4Al5 was prepared from the elements by reaction in niobium ampoules. The structure was refined from single-crystal data, which indicate the formation of a new structure type in the orthorhombic crystal system [ a = 1814.49(10), b = 431.64(4), c = 1102.47(4) pm] with space group Pnma ( wR2 = 0.0251, 1666 F2 values, 68 parameters). Full ordering of the transition-metal and aluminum sites was observed. The compound can be described as a polar intermetallic phase with a polyanionic [Pd4Al5] δ- network; however, a quite unique bonding situation was found within this framework. In addition to the usual Pd-Al bonding, significant contributions to the stability of the framework caused by homoatomic Pd-Pd and Al-Al interactions can also be found. Structural relaxation confirmed the electronic stability and predicted the compound to be a metallic conductor. [ABSTRACT FROM AUTHOR]

Ta3Ru5B2, Zr2.86(5)Ru5.14(5)B2, and Hf2.83(2)Ru5.17(2)B2 have been successfully synthesized as polycrystalline powders as well as single crystals and characterized by powder and single- crystal X-ray diffraction and EDX analysis. Furthermore, their electronic structures and bonding characteristics have been analyzed by DFT calculations. The three phases are isotypic and crystallize with a Ti3Co5B2-type structure (space group P4/mbm). Their electronic densities of states, which all possess a large pseudogap at the Fermi level, closely follow the rigid band model. Bonding analyses indicated that Ru-B and Ru-M (M = Zr, Hf, Ta) heteroatomic interactions are mainly responsible for their structural stability and that the homoatomic M-M interactions behave differently when connecting either two tetragonal or two pentagonal Ru prisms at the same distance. [ABSTRACT FROM AUTHOR]

Single crystals and polycrystalline samples of (Nb2- xSc x)4 gNb2 aRu5B2 (1 ≤ x < 2), Nb3- xM xRu5B2 (M = Ti, V; x ≈ 1), and Nb2+ xM1- xRu5B2 (M = Cr, Mn, Fe, Co, Ni; 0 < x ≤ 0.5) were synthesized from the elements and characterized by single-crystal and powder X-ray diffraction as well as energy-dispersive X-ray analysis. These phases are substitutional variants of the recently reported Nb3Ru5B2 phase and crystallize in the Ti3Co5B2-type structure (tetragonal, space group P4/ mbm, no. 127). The structure consists of layers of ruthenium atoms that build trigonal, tetragonal, and pentagonal prisms, in which the other atoms are incorporated. The larger 3d metals, Sc, Ti, and V are found on the larger pentagonal prisms, together with niobium, and also (except for Sc) on the tetragonal prisms. The smaller 3d metals, Cr-Ni, are only found on the tetragonal prisms, but also mix with niobium. DFT calculations on the ternary phase Nb3Ru5B2 suggested that the reason for this site mixing can be found in its electronic structure and the application of the rigid band model proposed a valence electron (VE) range between ca. 58 and 64 for the derived stable phases. All synthesized quaternary phases fit very well within this VE range. [ABSTRACT FROM AUTHOR]

Eu2Ni8Si3 and its anti‐type representative Sr2Pt3Al8 were synthesized from the elements. They crystallize in the tetragonal crystal system with space group P42/nmc and with lattice parameters of a=997.9(1) and c=747.6(1) pm (Eu2Ni8Si3) as well as a=1082.9(2) and c=823.3(2) pm (Sr2Pt3Al8). Both compounds were investigated via single crystal X‐ray diffraction, indicating slight Si/Ni mixing for the silicide. Sr2Pt3Al8 exhibits a temperature independent magnetic susceptibility, suggesting superimposed dia‐ and Pauli‐paramagnetic contributions. The independent Al and Pt sites of the platinide were further characterized by 27Al and 195Pt solid‐state NMR spectroscopy, which were assigned with the help of electronic structure calculations. ICOHP calculations and Bader charges were used to analyze the bonding situation. Eu2Ni8Si3 in contrast is paramagnetic with a ferromagnetic transition at TC=46.9(2) K and exhibits an effective magnetic moment of μeff=6.61(1) μB per Eu atom. The latter is in line with an intermediate valence that was further proven by 151Eu Mößbauer spectroscopic investigations. At 300 K, the refined Eu2+/Eu3+ ratios are 60 %/40 %, at 78 K 62 % and 38 % (Eu2+/Eu3+) are observed, being in line with the ratio deduced from the magnetic susceptibility. Finally, at 6 K a ratio of 68 % Eu2+ and 32 % Eu3+ was observed. Below the Curie temperature, the Eu2+ signal shows a full magnetic hyperfine splitting, with an internal magnetic field value of B0=28.4 T. [ABSTRACT FROM AUTHOR]

The CsCl/LiCl system has been studied for over a century now. Numerous phases have been predicted - only three have hitherto been found. We present the synthesis and single-crystal structure of the cesium lithium pentachloride Cs 3 Li 2 Cl 5 , predicted earlier but with a different structure. The anhydrous new phase readily reacts to Cs 3 LiCl 4 · 4H 2 O in air. The tetrahydrate can also be obtained through the simplest, most inexpensive and green synthesis possible: an immediate, room-temperature mechanosynthesis from only CsCl and LiCl (3 : 1) in air. Differential scanning calorimetry (DSC) and thermogravimetric analyses (TGA), as well as in situ temperature-dependent powder X-ray diffraction studies on this second ever reported ternary alkali chloride hydrate allowed for a revision of the CsCl/LiCl phase diagram. Density of states and total energy calculations further elucidate the new alkali chlorides and update the relative stability of previous structure predictions.