1
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Schenk FM, Zellweger T, Kumaar D, Bošković D, Wintersteller S, Solokha P, De Negri S, Emboras A, Wood V, Yarema M. Phase-Change Memory from Molecular Tellurides. ACS Nano 2024; 18:1063-1072. [PMID: 38117038 PMCID: PMC10786157 DOI: 10.1021/acsnano.3c10312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 12/13/2023] [Accepted: 12/15/2023] [Indexed: 12/21/2023]
Abstract
Phase-change memory (PCM) is an emerging memory technology based on the resistance contrast between the crystalline and amorphous states of a material. Further development and realization of PCM as a mainstream memory technology rely on innovative materials and inexpensive fabrication methods. Here, we propose a generalizable and scalable solution-processing approach to synthesize phase-change telluride inks in order to meet demands for high-throughput material screening, increased energy efficiency, and advanced device architectures. Bulk tellurides, such as Sb2Te3, GeTe, Sc2Te3, and TiTe2, are dissolved and purified to obtain inks of molecular metal telluride complexes. This allowed us to unlock a wide range of solution-processed ternary tellurides by the simple mixing of binary inks. We demonstrate accurate and quantitative composition control, including prototype materials (Ge-Sb-Te) and emerging rare-earth-metal telluride-doped materials (Sc-Sb-Te). Spin-coating and annealing convert ink formulations into high-quality, phase-pure telluride films with preferred orientation along the (00l) direction. Deposition engineering of liquid tellurides enables thickness-tunable films, infilling of nanoscale vias, and film preparation on flexible substrates. Finally, we demonstrate cyclable and non-volatile prototype memory devices, achieving performance indicators such as resistance contrast and low reset energy on par with state-of-the-art sputtered PCM layers.
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Affiliation(s)
- Florian M Schenk
- Chemistry and Materials Design Group, Institute for Electronics, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, CH-8092 Zurich, Switzerland
| | - Till Zellweger
- Integrated Systems Laboratory, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, CH-8092 Zurich, Switzerland
| | - Dhananjeya Kumaar
- Chemistry and Materials Design Group, Institute for Electronics, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, CH-8092 Zurich, Switzerland
| | - Darijan Bošković
- Chemistry and Materials Design Group, Institute for Electronics, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, CH-8092 Zurich, Switzerland
| | - Simon Wintersteller
- Chemistry and Materials Design Group, Institute for Electronics, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, CH-8092 Zurich, Switzerland
| | - Pavlo Solokha
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, I-16146 Genova, Italy
| | - Serena De Negri
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, I-16146 Genova, Italy
| | - Alexandros Emboras
- Integrated Systems Laboratory, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, CH-8092 Zurich, Switzerland
| | - Vanessa Wood
- Materials and Device Engineering Group, Institute for Electronics, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, CH-8092 Zurich, Switzerland
| | - Maksym Yarema
- Chemistry and Materials Design Group, Institute for Electronics, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, CH-8092 Zurich, Switzerland
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2
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Prabhakaran A, Dhanabalan B, Andrusenko I, Pianetti A, Lauciello S, Prato M, Marras S, Solokha P, Gemmi M, Brovelli S, Manna L, Arciniegas MP. Stable Sn-Based Hybrid Perovskite-Related Structures with Tunable Color Coordinates via Organic Cations in Low-Temperature Synthesis. ACS Energy Lett 2023; 8:2630-2640. [PMID: 37324542 PMCID: PMC10262684 DOI: 10.1021/acsenergylett.3c00791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 05/11/2023] [Indexed: 06/17/2023]
Abstract
Organic-inorganic Pb-free layered perovskites are efficient broadband emitters and thus are promising materials for lighting applications. However, their synthetic protocols require a controlled atmosphere, high temperature, and long preparation time. This hinders the potential tunability of their emission through organic cations, as is instead common practice in Pb-based structures. Here, we present a set of Sn-Br layered perovskite-related structures that display different chromaticity coordinates and photoluminescence quantum yield (PLQY) up to 80%, depending on the choice of the organic monocation. We first develop a synthetic protocol that is performed under air and at 4 °C, requiring only a few steps. X-ray and 3D electron diffraction analyses show that the structures exhibit diverse octahedra connectivity (disconnected and face-sharing) and thus optical properties, while preserving the organic-inorganic layer intercalation. These results provide key insight into a previously underexplored strategy to tune the color coordinates of Pb-free layered perovskites through organic cations with complex molecular configurations.
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Affiliation(s)
- Aarya Prabhakaran
- Center
for Convergent Technologies, Istituto Italiano
di Tecnologia, Via Morego 30, 16163 Genova, Italy
- Dipartimento
di Chimica e Chimica Industriale, Università
degli Studi di Genova, Via Dodecaneso, 31, 16146 Genova, Italy
| | - Balaji Dhanabalan
- Center
for Convergent Technologies, Istituto Italiano
di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Iryna Andrusenko
- Electron
Crystallography, Center for Materials Interfaces, Istituto Italiano di Tecnologia, Viale Rinaldo Piaggio 34, 56025 Pontedera, Italy
| | - Andrea Pianetti
- Dipartimento
di Scienza dei Materiali, Università
degli Studi di Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Simone Lauciello
- Center
for Convergent Technologies, Istituto Italiano
di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Mirko Prato
- Center
for Convergent Technologies, Istituto Italiano
di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Sergio Marras
- Center
for Convergent Technologies, Istituto Italiano
di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Pavlo Solokha
- Dipartimento
di Chimica e Chimica Industriale, Università
degli Studi di Genova, Via Dodecaneso, 31, 16146 Genova, Italy
| | - Mauro Gemmi
- Electron
Crystallography, Center for Materials Interfaces, Istituto Italiano di Tecnologia, Viale Rinaldo Piaggio 34, 56025 Pontedera, Italy
| | - Sergio Brovelli
- Dipartimento
di Scienza dei Materiali, Università
degli Studi di Milano-Bicocca, via R. Cozzi 55, 20125 Milano, Italy
| | - Liberato Manna
- Center
for Convergent Technologies, Istituto Italiano
di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Milena P. Arciniegas
- Center
for Convergent Technologies, Istituto Italiano
di Tecnologia, Via Morego 30, 16163 Genova, Italy
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3
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Mödlinger M, Provino A, Solokha P, Caglieris F, Ceccardi M, Macciò D, Pani M, Bernini C, Cavallo D, Ciccioli A, Manfrinetti P. Cu 3As: Uncommon Crystallographic Features, Low-Temperature Phase Transitions, Thermodynamic and Physical Properties. Materials (Basel) 2023; 16:2501. [PMID: 36984382 PMCID: PMC10051385 DOI: 10.3390/ma16062501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/09/2023] [Accepted: 03/15/2023] [Indexed: 06/18/2023]
Abstract
The formation and crystal structure of the binary Cu3As phase have been re-investigated. Some physical properties were then measured on both single crystal and polycrystalline bulk. Cu3As melts congruently at 835 °C. At room temperature (RT), this compound has been found to crystallize in the hexagonal Cu3P prototype (hP24, P63cm) with lattice parameters: a = 7.1393(1) Å and c = 7.3113(1) Å, rather than in the anti HoH3-type (hP24, P-3c1) as indicated in literature. A small compositional range of 74.0-75.5 at.% Cu (26.0-24.5 at.% As) was found for samples synthesized at 300 and 400 °C; a corresponding slight understoichiometry is found in one out of the four Cu atomic sites, leading to the final refined composition Cu2.882(1)As. The present results disprove a change in the crystal structure above RT actually reported in the phase diagram (from γ' to γ on heating). Instead, below RT, at T = 243 K (-30 °C), a first-order structural transition to a trigonal low-temperature superstructure, LT-Cu3-xAs (hP72, P-3c1) has been found. The LT polymorph is metrically related to the RT one, having the c lattice parameter three times larger: a = 7.110(2) Å and c = 21.879(4) Å. Both the high- and low-temperature polymorphs are characterized by the presence of a tridimensional (3D) uncommon and rigid Cu sublattice of the lonsdaleite type (Cu atoms tetrahedrally bonded), which remains almost unaffected by the structural change(s), and characteristic layers of triangular 'Cu3As'-units (each hosting one As atom at the center, interconnected each other by sharing the three vertices). The first-order transition is then followed by an additional structural change when lowering the temperature, which induces doubling of also the lattice parameter a. Differential scanning calorimetry nicely detects the first low-temperature structural change occurring at T = 243 K, with an associated enthalpy difference, ΔH(TR), of approximately 2 J/g (0.53 kJ/mol). Low-temperature electrical resistivity shows a typical metallic behavior; clear anomalies are detected in correspondence to the solid-state transformations. The Seebeck coefficient, measured as a function of temperature, highlights a conduction of n-type. The temperature dependence of the magnetic susceptibility displays an overall constant diamagnetic response.
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Affiliation(s)
| | - Alessia Provino
- Department of Chemistry, University of Genoa, 16146 Genoa, Italy
| | - Pavlo Solokha
- Department of Chemistry, University of Genoa, 16146 Genoa, Italy
| | - Federico Caglieris
- Department of Physics, University of Genoa, 16146 Genoa, Italy
- Institute SPIN-CNR, 16152 Genoa, Italy
| | | | - Daniele Macciò
- Department of Chemistry, University of Genoa, 16146 Genoa, Italy
| | - Marcella Pani
- Department of Chemistry, University of Genoa, 16146 Genoa, Italy
- Institute SPIN-CNR, 16152 Genoa, Italy
| | | | - Dario Cavallo
- Department of Chemistry, University of Genoa, 16146 Genoa, Italy
| | - Andrea Ciccioli
- Department of Chemistry, Sapienza University of Rome, 00185 Rome, Italy
| | - Pietro Manfrinetti
- Department of Chemistry, University of Genoa, 16146 Genoa, Italy
- Institute SPIN-CNR, 16152 Genoa, Italy
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4
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Freccero R, Pereira LCJ, Solokha P, De Negri S. Flux Growth, Crystal Structure, and Chemical Bonding of Yb 2PdGe 3, an AlB 2 Superstructure within the Rare-Earth Series. Inorg Chem 2023; 62:1988-1999. [PMID: 36662518 PMCID: PMC9906778 DOI: 10.1021/acs.inorgchem.2c03303] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The complete structure revision of the RE2PdGe3 (RE = rare-earth metal) series revealed that Yb2PdGe3 is the only AlB2 ordered superstructure. Good-quality single crystals of this compound were successfully grown from molten indium flux, enabling accurate single-crystal investigations. Yb2PdGe3 crystallizes with the Ce2CoSi3-type structure in the hexagonal space group P6/mmm (no. 191) with lattice parameters a = 8.468(1) Å and c = 4.0747(7) Å. This structure is a four-order derivative of AlB2, composed of planar ∞2[PdGe3] honeycomb layers spaced by Yb species, located at the center of Ge6 and Ge4Pd2 hexagons. A superconducting transition is observed below the critical temperature of 4 K. A divalent state of Yb is deduced from magnetic susceptibility measurements below room temperature, which indicate an almost nonmagnetic behavior. A charge transfer from Yb to Pd and Ge was evidenced by the Quantum Theory of Atoms in Molecules (QTAIM) effective charges; polar four-atomic Ge-Pd/Yb and two-atomic Pd-Yb bonds were observed from the ELI-D (electron localizability indicator), partial ELI-D, and ELI-D/QTAIM intersections. The bonding interactions between Ge atoms within regular Ge6 hexagons are found to be intermediate between single bonds, as in elemental Ge, and higher-order bonds in the hypothetic Ge6H6 and Ge66- aromatic molecules.
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Affiliation(s)
- Riccardo Freccero
- Dipartimento
di Chimica e Chimica Industriale, Università
degli Studi di Genova, Via Dodecaneso 31, I-16146Genova, Italy,riccardo.freccero@.unige.it
| | - Laura C. J. Pereira
- Centro
de Ciências e Tecnologias Nucleares, Department of Engenharia
e Ciências Nucleares, Instituto Superior Técnico, Universidade Lisboa, Estrada N acional 10, 2695-066Bobadela, Portugal
| | - Pavlo Solokha
- Dipartimento
di Chimica e Chimica Industriale, Università
degli Studi di Genova, Via Dodecaneso 31, I-16146Genova, Italy
| | - Serena De Negri
- Dipartimento
di Chimica e Chimica Industriale, Università
degli Studi di Genova, Via Dodecaneso 31, I-16146Genova, Italy
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5
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Solokha P, De Negri S, Freccero R. Architecture of rare earth-rich complex intermetallics based on polyicosahedral clusters. Acta Cryst Sect A 2022. [DOI: 10.1107/s2053273322091628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
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6
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Freccero R, Solokha P, De Negri S. Unpredicted but It Exists: Trigonal Sc 2Ru with a Significant Metal-Metal Charge Transfer. Inorg Chem 2021; 60:10084-10088. [PMID: 34240596 PMCID: PMC8389775 DOI: 10.1021/acs.inorgchem.1c01168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
The Sc2Ru compound, obtained by high-temperature synthesis,
was found to crystallize in a new trigonal hP45 structure
type [space group P3̅m1; a = 9.3583(9) Å and c = 11.285(1)
Å]: Ru@Sc8 cubes, Ru@Sc12 icosahedra, and
uncommon Ru@Sc10 sphenocoronae are the building blocks
of a unique motif tiling the whole crystal space. According to density
functional theory studies, Sc2Ru is a metallic compound
characterized by multicenter interactions: a significant charge transfer
occurs from Sc to Ru, indicating an unexpectedly strong ionic character
of the interactions between the two transition metals. Energy calculations
support our experimental results in terms of stability of this compound,
contributing to the recurrent discussion on the limits of the high-throughput
first-principles calculations for metallic materials design. A strong metal (Sc) to metal (Ru) charge transfer
occurs
for the new Sc2Ru compound, indicating a significant ionic contribution
to the bond. The Sc2Ru trigonal crystal structure features
a unique structural motif built up by Ru-centered simple cubes and
icosahedra connected through hybrid sphenocorona polyhedra. This investigation
represents also a little food for thought on the interplay between
the experiments and theoretical prediction in metallic materials design.
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Affiliation(s)
- Riccardo Freccero
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova,via Dodecaneso 31, Genova 16146, Italy
| | - Pavlo Solokha
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova,via Dodecaneso 31, Genova 16146, Italy
| | - Serena De Negri
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova,via Dodecaneso 31, Genova 16146, Italy
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7
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Abstract
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The new intermetallic
compound Eu2Pd2Sn has
been investigated. A single crystal was selected from the alloy and
was analyzed by single-crystal X-ray diffraction, revealing that this
compound possesses the noncentrosymmetric Ca2Pd2Ge structure type being, so far, the only rare-earth-based representative.
Bonding analysis, performed on the basis of DOS and (I)COHP, reveals
the presence of strong covalent Sn–Pd bonds in addition to
linear and equidistant Pd–Pd chains. The incomplete ionization
of Eu leads to its participation in weaker covalent interactions.
The magnetic effective moment, extracted from the magnetic susceptibility χ(T) is μeff = 7.87
μB, close to the free ion Eu2+ value (μeff = 7.94 μB). The maximum
of χ(T) at TN ∼
13 K indicates an antiferromagnetic behavior below this temperature.
A coincident sharp anomaly in the specific heat CP(T) emerges from a broad anomaly centered
at around 10 K. From the reduced jump in the heat capacity at TN a scenario of a transition to an incommensurate
antiferromagnetic phase below TN followed
by a commensurate configuration below 10 K is suggested. A new intermetallic compound, Eu2Pd2Sn, is so far the only rare-earth representative of the Ca2Pd2Ge structure type. Synthesis and characterization of
the structure, together with magnetic properties, are discussed.
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Affiliation(s)
- Mauro Giovannini
- Department of Chemistry, University of Genova, Via Dodecaneso 31, 16146 Genova, Italy
| | - Ivan Čurlík
- Faculty of Humanities and Natural Sciences, University of Prešov, 17 Novembra 1, 080 01 Prešov, Slovakia
| | - Riccardo Freccero
- Department of Chemistry, University of Genova, Via Dodecaneso 31, 16146 Genova, Italy
| | - Pavlo Solokha
- Department of Chemistry, University of Genova, Via Dodecaneso 31, 16146 Genova, Italy
| | - Marian Reiffers
- Faculty of Humanities and Natural Sciences, University of Prešov, 17 Novembra 1, 080 01 Prešov, Slovakia.,Institute of Experimental Physics, Slovak Academy of Science, Watsonova 47, 040 01 Košice, Slovakia
| | - Julian Sereni
- Department of Physics, CAB-CNEA, CONICET, IB-UNCuyo, 8400 S. C. de Bariloche, Argentina
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8
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Freccero R, De Negri S, Rogl G, Binder G, Michor H, Rogl PF, Saccone A, Solokha P. La 2Pd 3Ge 5 and Nd 2Pd 3Ge 5 Compounds: Chemical Bonding and Physical Properties. Inorg Chem 2021; 60:3345-3354. [PMID: 33570929 PMCID: PMC8023660 DOI: 10.1021/acs.inorgchem.0c03744] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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The two La2Pd3Ge5 and Nd2Pd3Ge5 compounds, crystallizing in the oI40-U2Co3Ge5 crystal structure,
were targeted for analysis of their chemical bonding and physical
properties. The compounds of interest were obtained by arc melting
and characterized by differential thermal analysis, scanning electron
microscopy, and X-ray diffraction both on powder and on a single crystal
(for the La analogue), to ensure the high quality of the samples and
accurate crystallographic data. Chemical bonding was studied by analyzing
the electronic structure and effective QTAIM charges of La2Pd3Ge5. A significant charge transfer mainly
occurs from La to Pd so that Ge species assume tiny negative charges.
This result, together with the -(I)COHP analysis, suggests that, in
addition to the expected homopolar Ge bonds within zigzag chains,
heteropolar interactions between Ge and the surrounding La and Pd
occur with multicenter character. Covalent La–Pd interactions
increase the complexity of chemical bonding, which could not be adequately
described by the simplified, formally obeyed, Zintl–Klemm scheme.
Electric resistivity, specific heat, magnetization, and magnetic susceptibility
as a function of temperature indicate for both compounds a metallic-like
behavior. For Nd2Pd3Ge5, two low-temperature
phase transitions are detected, leading to an antiferromagnetic ground
state. The chemical bonding and physical properties
of the two
isotypic R2Pd3Ge5 (R = La and Nd) intermetallics are presented. La2Pd3Ge5 shows polar Ge−Pd/La multicenter interactions
in addition to covalent Ge−Ge bonds. The bonding scenario is
further complicated by the fact that Pd and La are also covalently
interacting. For Nd2Pd3Ge5, an antiferromagnetic
ground state is established after a long-range magnetic ordering (at
∼7.5 K) followed by a spin-reorientation transition (at ∼6.2
K).
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Affiliation(s)
- Riccardo Freccero
- Università degli Studi di Genova, Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, I-16146 Genova, Italy
| | - Serena De Negri
- Università degli Studi di Genova, Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, I-16146 Genova, Italy
| | - Gerda Rogl
- Institute of Materials Chemistry, University of Vienna, Währingerstraße 42, A-1090 Vienna, Austria
| | - Georg Binder
- Institute of Solid State Physics, TU Wien, Wiedner Hauptstraße, 8-10, A-1040 Wien, Austria
| | - Herwig Michor
- Institute of Solid State Physics, TU Wien, Wiedner Hauptstraße, 8-10, A-1040 Wien, Austria
| | - Peter F Rogl
- Institute of Materials Chemistry, University of Vienna, Währingerstraße 42, A-1090 Vienna, Austria
| | - Adriana Saccone
- Università degli Studi di Genova, Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, I-16146 Genova, Italy
| | - Pavlo Solokha
- Università degli Studi di Genova, Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, I-16146 Genova, Italy
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9
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Freccero R, De Negri S, Saccone A, Solokha P. Solid state interactions in the La-Au-Mg system: phase equilibria, novel compounds and chemical bonding. Dalton Trans 2020; 49:12056-12067. [PMID: 32815954 DOI: 10.1039/d0dt02359k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Gold intermetallic chemistry is very rich, covering different classes of compounds ranging from the Hume-Rothery to Zintl phases to polar intermetallics to quasicrystals. Au's relativistic effects are frequently mentioned as responsible for the peculiar structural and physical properties of its compounds, nonetheless the aspects of chemical bonding are far to be clearly understood. In this work, the La-Au-Mg system was targeted for the discovery of new gold intermetallics and their structural and chemical bonding characterization. Studies on solid state interactions resulted in the construction of a partial La-Au-Mg isothermal section at 400 °C. The high reactivity between the constituents is reflected by the formation of five intermetallic compounds in the concentration range of less than 50 at% of Au. A complete crystallographic study was conducted for four of them, namely La1.82Au3+xMg14.36-x (0 ≤ x ≤ 0.90, hP42-3.64-CeMg10.3), La3Au4-xMg12+x (0 ≤ x ≤ 0.75, hP38-Gd3Ru4Al12), LaAuMg2 (oS16-MgCuAl2) and LaAu1+xMg1-x (0 ≤ x ≤ 0.15, hP9-ZrNiAl). A unifying description based on the different stacking sequences of equal slabs along the c-axis is proposed for these intermetallics. Chemical bonding in LaAuMg2 was studied by following the position space approach and including relativistic effects. Among the peculiarities of this LaMg2Au auride, there are two-atomic La-Au bonds showing a classical polar covalent character and that form distorted hexagonal planar layers and multi-atomic bonds involving Mg species. One of these is interpreted as a Mg-Mg bond supported by the neighbouring La and Au atoms, explaining the Mg reduced oxidation state (close to +1) in this compound.
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Affiliation(s)
- R Freccero
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova, Italy.
| | - S De Negri
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova, Italy.
| | - A Saccone
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova, Italy.
| | - P Solokha
- Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, via Dodecaneso 31, 16146 Genova, Italy.
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10
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Freccero R, Solokha P, De Negri S, Saccone A, Grin Y, Wagner FR. Polar‐Covalent Bonding Beyond the Zintl Picture in Intermetallic Rare‐Earth Germanides. Chemistry 2019; 25:6600-6612. [DOI: 10.1002/chem.201900510] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Indexed: 11/06/2022]
Affiliation(s)
- Riccardo Freccero
- Dipartimento di Chimica e Chimica IndustrialeUniversità degli Studi di Genova Via Dodecaneso 31 16146 Genova Italy
- Max-Planck-Institut für Chemische Physik fester Stoffe Nöthnitzer Straße 40 01187 Dresden Germany
| | - Pavlo Solokha
- Dipartimento di Chimica e Chimica IndustrialeUniversità degli Studi di Genova Via Dodecaneso 31 16146 Genova Italy
| | - Serena De Negri
- Dipartimento di Chimica e Chimica IndustrialeUniversità degli Studi di Genova Via Dodecaneso 31 16146 Genova Italy
| | - Adriana Saccone
- Dipartimento di Chimica e Chimica IndustrialeUniversità degli Studi di Genova Via Dodecaneso 31 16146 Genova Italy
| | - Yuri Grin
- Max-Planck-Institut für Chemische Physik fester Stoffe Nöthnitzer Straße 40 01187 Dresden Germany
| | - Frank R. Wagner
- Max-Planck-Institut für Chemische Physik fester Stoffe Nöthnitzer Straße 40 01187 Dresden Germany
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11
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Muts IR, Hlukhyy V, Galadzhun YV, Solokha P, Seidel S, Hoffmann RD, Pöttgen R, Zaremba VI. SrPt 3In 2– an orthorhombically distorted coloring variant of SrIn 5. Dalton Trans 2019; 48:11411-11420. [DOI: 10.1039/c9dt01808e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The new intermetallic phase SrPt3In2was synthesized by induction-melting of the elements in a sealed tantalum ampoule followed by long-term annealing for crystal growth.
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Affiliation(s)
- Ihor R. Muts
- Department of Life Safety
- Ivan Franko National University of Lviv
- 79000 Lviv
- Ukraine
| | - Viktor Hlukhyy
- Department of Chemistry
- Technische Universität München
- 85747 Garching
- Germany
| | | | - Pavlo Solokha
- Dipartimento di Chimica e Chimica Industriale
- Università degli Studi di Genova
- 16146 Genova
- Italy
| | - Stefan Seidel
- Institut für Anorganische und Analytische Chemie
- Universität Münster
- D-48149 Münster
- Germany
| | - Rolf-Dieter Hoffmann
- Institut für Anorganische und Analytische Chemie
- Universität Münster
- D-48149 Münster
- Germany
| | - Rainer Pöttgen
- Institut für Anorganische und Analytische Chemie
- Universität Münster
- D-48149 Münster
- Germany
| | - Vasyl’ I. Zaremba
- Inorganic Chemistry Department
- Ivan Franko National University of Lviv
- 79005 Lviv
- Ukraine
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12
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Akhmetshina T, Solokha P, Eremin R, Blatov V, Proserpio D, De Negri S, Saccone A. Nanocluster model and its application for crystal structure prediction of complex intermetallics. Acta Crystallogr A Found Adv 2018. [DOI: 10.1107/s2053273318094391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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13
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Solokha P, Minetti R, De Negri S, Pereira LCJ, Gonçalves AP, Saccone A. The
R
MgSn
2
Series of Compounds (
R
= Rare Earth Metal): Synthesis, Crystal Structure, and Magnetic Measurements. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201700280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Pavlo Solokha
- Dipartimento di Chimica e Chimica Industriale Università di Genova via Dodecaneso 31 16146 Genova Italy
| | - Riccardo Minetti
- Dipartimento di Chimica e Chimica Industriale Università di Genova via Dodecaneso 31 16146 Genova Italy
| | - Serena De Negri
- Dipartimento di Chimica e Chimica Industriale Università di Genova via Dodecaneso 31 16146 Genova Italy
| | - Laura Cristina J. Pereira
- Centro de Ciências e Tecnologias Nucleares Instituto Superior Técnico, EN 10 Universidade de Lisboa ao Km 139.7 2695‐066 Bobadela LRS Portugal
| | - Antonio P. Gonçalves
- Centro de Ciências e Tecnologias Nucleares Instituto Superior Técnico, EN 10 Universidade de Lisboa ao Km 139.7 2695‐066 Bobadela LRS Portugal
| | - Adriana Saccone
- Dipartimento di Chimica e Chimica Industriale Università di Genova via Dodecaneso 31 16146 Genova Italy
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14
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De Negri S, Solokha P, Minetti R, Skrobańska M, Saccone A. Isothermal section of the La-Mg-Sn system at 500 °C and crystal structure of the new ternary stannide LaMgSn 2. J SOLID STATE CHEM 2017. [DOI: 10.1016/j.jssc.2017.01.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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15
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Freccero R, Solokha P, Proserpio DM, Saccone A, De Negri S. A new glance on R2MGe6(R = rare earth metal, M = another metal) compounds. An experimental and theoretical study of R2PdGe6germanides. Dalton Trans 2017; 46:14021-14033. [DOI: 10.1039/c7dt02686b] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The R2PdGe6series (R = rare earth metal) was analyzed from structural and theoretical point of view.
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Affiliation(s)
- Riccardo Freccero
- Università di Genova
- Dipartimento di Chimica e Chimica Industriale
- 16146 Genova
- Italy
| | - Pavlo Solokha
- Università di Genova
- Dipartimento di Chimica e Chimica Industriale
- 16146 Genova
- Italy
| | - Davide M. Proserpio
- Università degli Studi di Milano
- Dipartimento di Chimica
- 20133 Milano
- Italy
- Samara Center for Theoretical Materials Science (SCTMS)
| | - Adriana Saccone
- Università di Genova
- Dipartimento di Chimica e Chimica Industriale
- 16146 Genova
- Italy
| | - Serena De Negri
- Università di Genova
- Dipartimento di Chimica e Chimica Industriale
- 16146 Genova
- Italy
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16
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Abstract
Atom order in the crystal structures of Yb2Cu2-xMg (x = 0.17; Mo2FeB2-type; P4/mbm; a = 0.75592(2) nm; c = 0.40282(1) nm) and Yb9+xCuMg4-x (x = 0.034; Hf9Mo4B-type; P63/mmc; a = 1.0169(5) nm; c = 1.0290(5) nm) was determined from powder and X-ray single-crystal counter data analyses supported by electron probe microanalyses. Among the group of the so-called κ-phases, Yb9+xCuMg4-x is the first representative formed by a lanthanoid element. The structure of this κ-phase can be viewed as a typical network of corner-connected empty Yb6-octahedra, which encompass Yb6Mg6-icosahedra (filled by a mix of Mg/Yb atoms) and Yb6-trigonal prisms centered by Cu atoms to complete the three-dimensional metal framework. From another point of view, the same structure is considered as built from infinite polyicosahedral columns of Yb9Mg4 composition with Cu atoms located in trigonal prismatic interstices, highlighting similarities with other Yb-rich Yb-Cu-Mg phases. Density functional theory (DFT) calculations classify Yb9CuMg4 as a polar intermetallic. Metallic-like behavior is inferred from the Sommerfeld constant, γ = 49.2 mJ/mol·K(2), derived from the electronic density of states, calculated at the Fermi level. DFT integration of the f-density of states indicates almost completely filled f-states, revealing 13.6 and 13.7 electrons in the valence band for Yb1 and Yb2 atoms, respectively, close to the Yb(2+) ground state ((1)S0) for both Yb atoms. Magnetic susceptibility data recorded on the same compound are consistent with a nonmagnetic divalent Yb(2+) state. Temperature-dependent heat capacity data display a metallic behavior characterized by a small Sommerfeld constant γ = 64.8 mJ/mol·K(2) and a rather low Debye temperature ΘD = 140 K as typical for soft materials.
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Affiliation(s)
- Serena De Negri
- Dipartimento di Chimica e Chimica Industriale, Università di Genova , Via Dodecaneso 31, I-16146 Genova, Italy
| | - Vitaliy Romaka
- Department of Materials Science and Engineering, Lviv Polytechnic National University , Ustiyanovycha Str. 5, 79013 Lviv, Ukraine
| | - Pavlo Solokha
- Dipartimento di Chimica e Chimica Industriale, Università di Genova , Via Dodecaneso 31, I-16146 Genova, Italy
| | - Adriana Saccone
- Dipartimento di Chimica e Chimica Industriale, Università di Genova , Via Dodecaneso 31, I-16146 Genova, Italy
| | - Gerald Giester
- Institute of Mineralogy and Crystallography, University of Vienna , Althanstrasse14, A-1090 Wien, Austria
| | - Herwig Michor
- Institute of Solid State Physics, TU Wien , Wiedner Hauptstraße 8-10, A-1090 Wien, Austria
| | - Peter F Rogl
- Institute of Materials Chemistry and Research, University of Vienna , Währingerstraße 42, A-1090 Wien, Austria
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17
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Wrubl F, Manfrinetti P, Pani M, Solokha P, Saccone A. Crystal Chemistry of the New Families of Interstitial Compounds R6Mg23C (R = La, Ce, Pr, Nd, Sm, or Gd) and Ce6Mg23Z (Z = C, Si, Ge, Sn, Pb, P, As, or Sb). Inorg Chem 2016; 55:191-204. [PMID: 26671746 DOI: 10.1021/acs.inorgchem.5b02114] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The crystal chemical features of the new series of compounds R6Mg23C with R = La-Sm or Gd and Ce6Mg23Z with Z = C, Si, Ge, Sn, Pb, P, As, or Sb have been studied by means of single-crystal and powder X-ray diffraction techniques. All phases crystallize with the cubic Zr6Zn23Si prototype (cF120, space group Fm3̅m, Z = 4), a filled variant of the Th6Mn23 structure. While no Th6Mn23-type binary rare earth-magnesium compound is known to exist, the addition of a third element Z (only 3 atom %), located into the octahedral cavity of the Th6Mn23 cell (Wyckoff site 4a), stabilizes this structural arrangement and makes possible the formation of the ternary R6Mg23Z compounds. The results of both structural and topological analyses as well as of LMTO electronic structure calculations show that the interstitial element plays a crucial role in the stability of these phases, forming a strongly bonded [R6Z] octahedral moiety spaced by zeolite cage-like [Mg45] clusters. Considering these two building units, the crystal structure of these apparently complex intermetallics can be simplified to the NaCl-type topology. Moreover, a structural relationship between RMg3 and R6Mg23C compounds has been unveiled; the latter can be described as substitutional derivatives of the former. The geometrical distortions and the consequent symmetry reduction that accompany this transformation are explicitly described by means of the Bärnighausen formalism within group theory.
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Affiliation(s)
- Federico Wrubl
- Dipartimento di Chimica e Chimica Industriale, Università di Genova , Via Dodecaneso 31, 16146 Genova, Italy
| | - Pietro Manfrinetti
- Dipartimento di Chimica e Chimica Industriale, Università di Genova , Via Dodecaneso 31, 16146 Genova, Italy.,CNR-SPIN , Corso Perrone 24, 16152 Genova, Italy
| | - Marcella Pani
- Dipartimento di Chimica e Chimica Industriale, Università di Genova , Via Dodecaneso 31, 16146 Genova, Italy.,CNR-SPIN , Corso Perrone 24, 16152 Genova, Italy
| | - Pavlo Solokha
- Dipartimento di Chimica e Chimica Industriale, Università di Genova , Via Dodecaneso 31, 16146 Genova, Italy
| | - Adriana Saccone
- Dipartimento di Chimica e Chimica Industriale, Università di Genova , Via Dodecaneso 31, 16146 Genova, Italy
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18
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Solokha P, De Negri S, Minetti R, Proserpio D, Saccone A. Crystal structures of the new ternary stannides La3Mg4−Sn2+ and LaMg3−Sn2. J SOLID STATE CHEM 2016. [DOI: 10.1016/j.jssc.2015.11.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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19
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Abstract
Abstract
The crystal structure of the new Er6Zn23Ge intermetallic compound was established by X-ray diffraction analysis on a twinned crystal (space group Fm3̅m, Wyckoff sequence: f2edba, cF120–Zr6Zn23Si, a
=12.7726(6) Å). The crystal is composed of two nearly equal size domains, whose mutual orientation is described by a 180° rotation around the cubic [111] axis, i.e. a spinel-type twinning law, not common for intermetallics. Applying the nanocluster approach, Er6Ge octahedra and centered two-shell Zn45 clusters were found as structural building blocks, filling the crystal space in a NaCl-like arrangement. This description was adopted to interpret the twinning in terms of stacking faults in the fcc cubic close packed arrangement. Moreover, the assembly of the nanocluster units is proposed as a possible mechanism for crystal growth and twin formation, in agreement with the principle of the interface energy minimization. Experimental conditions such as supersaturation and co-formation of other phases are also considered as favorable factors for Er6Zn23Ge twin formation.
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Affiliation(s)
- Pavlo Solokha
- Università di Genova, Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, 16146 Genova, Italy
| | - Serena De Negri
- Università di Genova, Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, 16146 Genova, Italy
| | | | - Adriana Saccone
- Università di Genova, Dipartimento di Chimica e Chimica Industriale, Via Dodecaneso 31, 16146 Genova, Italy
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20
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Solokha P, De Negri S, Proserpio DM, Blatov VA, Saccone A. Vacancy Ordering as a Driving Factor for Structural Changes in Ternary Germanides: The New R2Zn1–xGe6 Series of Polar Intermetallics (R = Rare-Earth Metal). Inorg Chem 2015; 54:2411-24. [DOI: 10.1021/ic5030313] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pavlo Solokha
- Dipartimento
di Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso
31, 16146 Genova, Italy
| | - Serena De Negri
- Dipartimento
di Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso
31, 16146 Genova, Italy
| | - Davide M. Proserpio
- Dipartimento
di Chimica, Università degli Studi di Milano, Via Golgi
19, 20133 Milano, Italy
- Samara
Center for Theoretical Materials Science (SCTMS), Samara State University, Ac. Pavlov Street 1 Samara 443011, Russia
| | - Vladislav A. Blatov
- Samara
Center for Theoretical Materials Science (SCTMS), Samara State University, Ac. Pavlov Street 1 Samara 443011, Russia
| | - Adriana Saccone
- Dipartimento
di Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso
31, 16146 Genova, Italy
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21
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De Negri S, Solokha P, Skrobańska M, Proserpio D, Saccone A. Phase equilibria in the La–Mg–Ge system at 500°C and crystal structure of the new ternary compounds La11Mg2Ge7 and LaMg3−xGe2. J SOLID STATE CHEM 2014. [DOI: 10.1016/j.jssc.2014.06.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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22
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23
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Solokha P, De Negri S, Pavlyuk V, Saccone A, Fadda G. Synthesis and Crystallochemical Characterisation of the Intermetallic Phases La(Ag
x
Mg
1–
x
)
12
(0.11 ≤
x
≤ 0.21), LaAg
4+
x
Mg
2–
x
(–0.15 ≤
x
≤ 1.05) and LaAg
2+
x
Mg
2–
x
(0 <
x
≤ 0.45). Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200700] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Pavlo Solokha
- Dipartimento di Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, 16146 Genova, Italy, Fax: +39‐0103536163
| | - Serena De Negri
- Dipartimento di Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, 16146 Genova, Italy, Fax: +39‐0103536163
| | - Volodymyr Pavlyuk
- Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla and Mefodiya str. 6, 79005 Lviv, Ukraine
- Institute of Chemistry, Environment Protection and Biotechnology, Jan Dlugosz University, al. Armii Krajowej 13/15, 42200 Czestochowa, Poland
| | - Adriana Saccone
- Dipartimento di Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, 16146 Genova, Italy, Fax: +39‐0103536163
| | - Giuseppe Fadda
- Dipartimento di Metodi e Modelli Matematici per le Scienze Applicate, Università di Padova, Via Trieste 63, 35121 Padova, Italy
- Dipartimento di Fisica, Universita di Cagliari, S. P. Monserrato‐Sestu km 0.700, 09042 Monserrato (CA), Italy
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24
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Solokha P, De Negri S, Skrobanska M, Saccone A, Pavlyuk V, Proserpio DM. New Ternary Germanides La4Mg5Ge6 and La4Mg7Ge6: Crystal Structure and Chemical Bonding. Inorg Chem 2011; 51:207-14. [DOI: 10.1021/ic2014732] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pavlo Solokha
- Dipartimento di
Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, I-16146 Genova, Italy
| | - Serena De Negri
- Dipartimento di
Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, I-16146 Genova, Italy
| | - Monika Skrobanska
- Dipartimento di
Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, I-16146 Genova, Italy
| | - Adriana Saccone
- Dipartimento di
Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, I-16146 Genova, Italy
| | - Volodymyr Pavlyuk
- Department of Inorganic
Chemistry, Ivan Franko National University of Lviv, Kyryla and Mefodiya street 6, 79005 Lviv,
Ukraine
- Institute
of Chemistry
and Environment Protection, Jan Dlugosz University, al. Armii Krajowej 13/15, 42200 Czestochowa,
Poland
| | - Davide M. Proserpio
- Dipartimento
di
Chimica Strutturale e Stereochimica Inorganica, Università di Milano, Via Venezian 21, 20133
Milano, Italy
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Solokha P, De Negri S, Pavlyuk V, Saccone A. Anti-mackay polyicosahedral clusters in La-Ni-Mg ternary compounds: synthesis and crystal structure of the La(43)Ni(17)Mg(5) new intermetallic phase. Inorg Chem 2009; 48:11586-93. [PMID: 19916494 DOI: 10.1021/ic901422v] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The crystal structure of the complex La(43)Ni(17)Mg(5) ternary phase was solved and refined from X-ray single crystal diffraction data. It is characterized by a very large unit cell and represents a new structure type: La(43)Ni(17)Mg(5) - orthorhombic, Cmcm, oS260, a = 10.1895(3), b = 17.6044(14), c = 42.170(3) A, Z = 4, wR1 = 0.0598, wR2 = 0.0897, 4157 F(2) values, 176 variables. The crystal structures of the La-rich La-Ni-Mg intermetallic phases La(4)NiMg, La(23)Ni(7)Mg(4), and La(43)Ni(17)Mg(5) have been comparatively analyzed. The constitutive fragments of these structures are binary polyicosahedral core-shell clusters of Mg(4)La(22) and Mg(5)La(24) compositions together with binary polytetrahedral clusters of nickel and lanthanum atoms. The structures of the Mg-La clusters are described in detail as a unique feature of the analyzed intermetallic phases; the dodecahedral Voronoi polyhedra are proposed as a useful tool to characterize polyicosahedral clusters. The arrangements of the building units in the studied phases show some regularities; particularly the i(4)3, i(5)3 and L-i(4) units, made up of polyicosahedral clusters and analogous to the Kreiner i(3) and L units, are proposed as structural blocks.
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Affiliation(s)
- Pavlo Solokha
- Dipartimento di Chimica e Chimica Industriale, Università di Genova, Via Dodecaneso 31, I-16146 Genova, Italy.
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Pavlyuk V, Solokha P, Zelinska O, Paul-Boncour V, Nowik-Zajac A. Ce20Mg19Zn81: a new structure type with a giant cubic cell. Acta Crystallogr C 2008; 64:i50-2. [PMID: 18599964 DOI: 10.1107/s0108270108015862] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2008] [Accepted: 05/26/2008] [Indexed: 11/11/2022] Open
Abstract
Icosacerium nonadecamagnesium henoctacontazinc, Ce(20)Mg(19)Zn(81), synthesized by fritting of the pure elements with subsequent arc melting, crystallizes with an unusually large cubic unit cell [space group F\overline{4}3m, a = 21.1979 (8) A] and represents a new structure type among the technologically important family of ternary rare earth-transition metal-magnesium intermetallics. The majority of atoms (two Ce and five Zn) display .3m site symmetry, two Ce and one Mg atom occupy three 2.mm positions, one Mg and one Zn have \overline{4}3m site symmetry, one Mg and three Zn atoms sit in ..m positions, and one Zn atom is in a general position. The Ce(20)Mg(19)Zn(81) structure can be described using the geometric concept of nested polyhedral units, by which it consists of four different polyhedral units, viz. A (Zn+Zn(4)+Zn(4)+Zn(12)+Ce(6)), B (Mg+Zn(12)+Ce(4)+Zn(24)+Ce(4)), C (Zn(4)+Zn(12)+Mg(6)) and D (Zn(4)+Zn(4)+Mg(12)+Ce(6)), with the outer construction unit being an octahedron or tetrahedron. All interatomic distances in the structure indicate metallic-type bonding.
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Affiliation(s)
- Volodymyr Pavlyuk
- Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla i Mefodiya Street 6, 79005 Lviv, Ukraine
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27
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Solokha P, De Negri S, Pavlyuk V, Saccone A, Marciniak B. Crystallochemistry of the novel two-layer RECuMg4 (RE=La, Tb) ternary compounds. J SOLID STATE CHEM 2007. [DOI: 10.1016/j.jssc.2007.09.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Solokha P, De Negri S, Saccone A, Pavlyuk V, Tedenac JC. Crystal Structure Investigation of RE–Ni–Zn Ternary Compounds (RE = La, Ce, Tb). Z Anorg Allg Chem 2007. [DOI: 10.1002/zaac.200600310] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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29
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Solokha P, De Negri S, Saccone A, Pavlyuk V, Marciniak B, Tedenac JC. Tb2Ni2Mg3: a new structure type derived from the Ru3Al2B2type. Acta Crystallogr C 2007; 63:i13-6. [PMID: 17284783 DOI: 10.1107/s0108270107001503] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Accepted: 01/11/2007] [Indexed: 11/11/2022] Open
Affiliation(s)
- Pavlo Solokha
- Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla i Mefodiya St. 6, 79005 Lviv, Ukraine.
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30
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Solokha P, Pavlyuk V, Saccone A, De Negri S, Prochwicz W, Marciniak B, Różycka-Sokołowska E. Rare earth–copper–magnesium compounds RECu9Mg2 (RE=Y, La–Nd, Sm–Ho, Yb) with ordered CeNi3-type structure. J SOLID STATE CHEM 2006. [DOI: 10.1016/j.jssc.2006.05.040] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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