1
|
Pavlyuk N, Milashius V, Kordan V, Pavlyuk V. Synthesis, crystal structure and hydrogenation properties of Mg xLi 3 - xB 48 - y ( x = 1.11, y = 0.40). Acta Crystallogr E Crystallogr Commun 2024; 80:10-13. [PMID: 38312165 PMCID: PMC10833378 DOI: 10.1107/s2056989023009969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/16/2023] [Indexed: 02/06/2024]
Abstract
The ternary magnesium/lithium boride, MgxLi3 - xB48 - y (x = 1.11, y = 0.40, idealized formula MgLi2B48), crystallizes as its own structure type in P43212, which is closely related to the structural family comprising α-AlB12, Be0.7Al1.1B22 and tetra-gonal β-boron. The asymmetric unit of title structure contains two statistical mixtures Mg/Li in Wyckoff sites 8b with relative occupancies Mg:Li = 0.495 (9):0.505 (9) and 4a with Mg:Li = 0.097 (8):0.903 (8). The boron atoms occupy 23 8b sites and two 4a sites. One of the latter sites has a partial occupancy factor of 0.61 (2). Both unique Mg/Li atoms adopt a twelvefold coordination environment in the form of truncated tetra-hedra (Laves polyhedra). These polyhedra are connected by triangular faces to four [B12] icosa-hedra. The boron atoms exhibit four kinds of polyhedra, namely penta-gonal pyramid (coordination number CN = 6), distorted tetra-gonal pyramid (CN = 5), bicapped hexa-gon (CN = 8) and gyrobifastigium (CN = 8). At the gas hydrogenation of MgLi2B48 alloy, formation of the eutectic composite hydride LiBH4+Mg(BH4)2 and amorphous boron is observed. In the temperature range 543-623 K, the hydride eutectics decompose, forming MgH2, LiH, MgB4, B and H2.
Collapse
Affiliation(s)
- Nazar Pavlyuk
- Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla i Mefodiya str., 6, 79005, Lviv, Ukraine
| | - Viktoria Milashius
- Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla i Mefodiya str., 6, 79005, Lviv, Ukraine
| | - Vasyl Kordan
- Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla i Mefodiya str., 6, 79005, Lviv, Ukraine
| | - Volodymyr Pavlyuk
- Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla i Mefodiya str., 6, 79005, Lviv, Ukraine
| |
Collapse
|
2
|
Zheng X, Yan D, Yi C, Zhu J, Zhang Q, Zhai J, Ma T, Zhu P, Li H, Gu L, Zhao Y, Yao Y, Shi Y, Yu X, Jin C. The discovery of a superhard P-type transparent semiconductor: Al 2.69B 50. MATERIALS HORIZONS 2022; 9:748-755. [PMID: 34881773 DOI: 10.1039/d1mh00975c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Superhard semiconductors have been long sought after for electronic device applications enduring extreme conditions, such as astronautics, due to their intrinsic toughness, high thermal and chemical stability. Here, we report the superhard p-type semiconductor Al2.69B50 single crystal with the determined Vickers hardness of ∼40.5 GPa under the load of 0.49 N, which is one of the hardest semiconductor compounds that have been ever found. With the direct band gap of 2.3 eV, Al2.69B50 exhibits excellent optical transmittance (>90%), covering the visible range from 459 nm to 760 nm and part of the infrared range, and also shows the high intensity of the photon emission in the visible light. Al2.69B50 is very stable, thermally and chemically, with an ultra-low density of ∼2.52 g cm-3, allowing for further extension of its applications. Such an assembly of various excellent properties within one material has great implication for high power electronic design and applications.
Collapse
Affiliation(s)
- Xu Zheng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Dayu Yan
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Changjiang Yi
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Jinlong Zhu
- Department of Physics, South University of Science and Technology of China, Shenzhen 518055, China
| | - Qinghua Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Junyi Zhai
- Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083, China
| | - Teng Ma
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Pinwen Zhu
- State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China
| | - Hui Li
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Lin Gu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
- Collaborative Innovation Center of Quantum Matter, Beijing 100190, China
| | - Yusheng Zhao
- Department of Physics, South University of Science and Technology of China, Shenzhen 518055, China
| | - Yugui Yao
- School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Youguo Shi
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Xiaohui Yu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| | - Changqing Jin
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
| |
Collapse
|
3
|
Novel photo-theranostic GdB6 nanoparticles for fluorescence imaging and NIR-photothermal therapy. CHINESE CHEM LETT 2021. [DOI: 10.1016/j.cclet.2021.04.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
4
|
Zhang G, Xu C, Wang M, Dong Y, Sun F, Ren X, Xu H, Zhao Y. Pressure effect of the mechanical, electronics and thermodynamic properties of Mg-B compounds A first-principles investigations. Sci Rep 2021; 11:6096. [PMID: 33731866 PMCID: PMC7969778 DOI: 10.1038/s41598-021-85654-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Accepted: 03/04/2021] [Indexed: 11/22/2022] Open
Abstract
First principle calculations were performed to investigate the structural, mechanical, electronic properties, and thermodynamic properties of three binary Mg–B compounds under pressure, by using the first principle method. The results implied that the structural parameters and the mechanical properties of the Mg–B compounds without pressure are well matched with the obtainable theoretically simulated values and experimental data. The obtained pressure–volume and energy–volume revealed that the three Mg–B compounds were mechanically stable, and the volume variation decreases with an increase in the boron content. The shear and volume deformation resistance indicated that the elastic constant Cij and bulk modulus B increased when the pressure increased up to 40 GPa, and that MgB7 had the strongest capacity to resist shear and volume deformation at zero pressure, which indicated the highest hardness. Meanwhile, MgB4 exhibited a ductility transformation behaviour at 30 GPa, and MgB2 and MgB7 displayed a brittle nature under all the considered pressure conditions. The anisotropy of the three Mg–B compounds under pressure were arranged as follows: MgB4 > MgB2 > MgB7. Moreover, the total density of states varied slightly and decreased with an increase in the pressure. The Debye temperature ΘD of the Mg–B compounds gradually increased with an increase in the pressure and the boron content. The temperature and pressure dependence of the heat capacity and the thermal expansion coefficient α were both obtained on the basis of Debye model under increased pressure from 0 to 40 GPa and increased temperatures. This paper brings a convenient understanding of the magnesium–boron alloys.
Collapse
Affiliation(s)
- GuoWei Zhang
- School of Materials Science and Engineering, North University of China, Taiyuan, 030051, Shanxi, China.
| | - Chao Xu
- School of Materials Science and Engineering, North University of China, Taiyuan, 030051, Shanxi, China
| | - MingJie Wang
- School of Materials Science and Engineering, North University of China, Taiyuan, 030051, Shanxi, China
| | - Ying Dong
- School of Materials Science and Engineering, North University of China, Taiyuan, 030051, Shanxi, China
| | - FengEr Sun
- School of Materials Science and Engineering, North University of China, Taiyuan, 030051, Shanxi, China
| | - XiaoYan Ren
- School of Materials Science and Engineering, North University of China, Taiyuan, 030051, Shanxi, China.,Department of mechanical engineering, Taiyuan Institute of Technology, Taiyuan, 030008, Shanxi, China
| | - Hong Xu
- School of Materials Science and Engineering, North University of China, Taiyuan, 030051, Shanxi, China
| | - YuHong Zhao
- School of Materials Science and Engineering, North University of China, Taiyuan, 030051, Shanxi, China
| |
Collapse
|
5
|
Ludwig M, Hillebrecht H. First-principles calculation of 11B solid-state NMR parameters of boron-rich compounds II: the orthorhombic phases MgB 7 and MgB 12C 2 and the boron modification γ-B 28. Phys Chem Chem Phys 2021; 23:3883-3897. [PMID: 33539490 DOI: 10.1039/d0cp06073a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Based on the work on referencing 11B nuclear magnetic resonance (NMR) spectra for molecular icosahedral boranes and the subsequent transfer to the rhombohedral boron-rich borides of the α-rB12 type, we show that the magic angle spinning (MAS) NMR spectra of boron-rich borides with four or five symmetry-independent boron atoms can also be calculated. The calculations are performed on the level of density functional theory (DFT) using the gauge-including projector-augmented wave (GIPAW) approach. As model compounds o-MgB12C2 and MgB7 are used, for which the experimental spectra could be calculated in excellent agreement with a deviation of 1 to 2 ppm. Based on the calculations, the different B atoms can be assigned to the respective signals, taking into account the quadrupolar coupling constants Cq from computation of the electric field gradient (EFG) with its main axis Vzz. It is shown that due to the specific geometric conditions of icosahedra, the magnitudes of Vzz for the boron atoms involved in exohedral B-B bonds to neighbouring icosahedra depend only on the valence electron density of the bond critical point and the distance. This also applies to the bonds to the interstitial B2 unit in MgB7, but not to bonds to the heteroatom of the C2 dumbbell in o-MgB12C2. Both results are in line with our previous observations for the rhombohedral species (α-rB12; B12X2 with X = P, As, O). Finally, the spectrum of γ-B28 was calculated, whose structure also contains B12 icosahedra and interstitial B2 dumbbells. Here, a very similar bonding situation is found for the icosahedron, but the calculations show that the situation for the B2 unit is clearly different. In general, the only parameter that needs to be varied to fit calculated and measured spectra is the linewidth, as this cannot be calculated. For the cases of o-MgB12C2 and MgB7 signal areas are related to corresponding site multiplicities. A prerequisite for the successful application of the chosen method seems to be the presence of a semiconductor with a sufficiently large band gap, which is the case for the compounds investigated.
Collapse
Affiliation(s)
- Martin Ludwig
- Institut für Anorganische und Analytische Chemie, Albert-Ludwigs-Universität, Albertstr. 21, 79104 Freiburg, Germany.
| | - Harald Hillebrecht
- Institut für Anorganische und Analytische Chemie, Albert-Ludwigs-Universität, Albertstr. 21, 79104 Freiburg, Germany.
| |
Collapse
|
6
|
Ovchinnikov A, Smetana V, Mudring AV. Metallic alloys at the edge of complexity: structural aspects, chemical bonding and physical properties. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:243002. [PMID: 31935688 DOI: 10.1088/1361-648x/ab6b87] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Complex metallic alloys belong to the vast family of intermetallic compounds and are hallmarked by extremely large unit cells and, in many cases, extensive crystallographic disorder. Early studies of complex intermetallics were focusing on the elucidation of their crystal structures and classification of the underlying building principles. More recently, ab initio computational analysis and detailed examination of the physical properties have become feasible and opened new perspectives for these materials. The present review paper provides a summary of the literature data on the reported compositions with exceptional structural complexity and their properties, and highlights the factors leading to the emergence of their crystal structures and the methods of characterization and systematization of these compounds.
Collapse
Affiliation(s)
- Alexander Ovchinnikov
- Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16 C, 10691 Stockholm, Sweden
| | | | | |
Collapse
|
7
|
Fan M, Wen Y, Ye D, Jin Z, Zhao P, Chen D, Lu X, He Q. Acid-Responsive H 2 -Releasing 2D MgB 2 Nanosheet for Therapeutic Synergy and Side Effect Attenuation of Gastric Cancer Chemotherapy. Adv Healthc Mater 2019; 8:e1900157. [PMID: 30968583 DOI: 10.1002/adhm.201900157] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 02/28/2019] [Indexed: 11/12/2022]
Abstract
The hydrogen molecule is recognized as a high potential to attenuate toxic side effects of chemotherapy and also enhance chemotherapeutic efficacy, and the development of a novel hydrogen-generating prodrug for facile, safe, and efficient hydrogen delivery is vitally important for combined hydrogenochemotherapy but is still challenging. Here, targeting gastric cancer, a 2D magnesium boride nanosheet (MBN) is synthesized as a new type of acid-responsive hydrogen-releasing prodrug by an ultrasound-assisted chemical etching route, which is used to realize hydrogenochemotherapy by combination of facile oral administration of polyvinylpyrrolidone (PVP)-encapsulating MBN (MBN@PVP) pills with routine intravenous injection of doxorubicin (DOX). The MBN@PVP pill has high stability in normal tissues/blood environments as well as high gastric acid-responsiveness with sustained release behavior, which matches well with its metabolism rate in the stomach in great favor of continuous and long-term hydrogen administration. Hydrogenochemotherapy with DOX+MBN@PVP has remarkably prolonged the survival time of gastric tumor-bearing mice by reducing the toxic side effects of chemotherapy. The mechanism for therapeutic synergy and side effect attenuation of hydrogenochemotherapy is discovered to be derived from the selectivity of hydrogen molecules in inhibiting aerobic respiration of gastric cells but activating aerobic respiration of normal cells including marrow mesenchymal stem cells and cardiac, hepatic, and splenic cells.
Collapse
Affiliation(s)
- Mingjian Fan
- Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound ImagingNational‐Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringHealth Science CenterShenzhen University No. 1066 Xueyuan Road, Nanshan District Shenzhen 518060 Guangdong China
| | - Yanyuan Wen
- Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound ImagingNational‐Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringHealth Science CenterShenzhen University No. 1066 Xueyuan Road, Nanshan District Shenzhen 518060 Guangdong China
| | - Dien Ye
- Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound ImagingNational‐Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringHealth Science CenterShenzhen University No. 1066 Xueyuan Road, Nanshan District Shenzhen 518060 Guangdong China
| | - Zhaokui Jin
- Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound ImagingNational‐Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringHealth Science CenterShenzhen University No. 1066 Xueyuan Road, Nanshan District Shenzhen 518060 Guangdong China
| | - Penghe Zhao
- Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound ImagingNational‐Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringHealth Science CenterShenzhen University No. 1066 Xueyuan Road, Nanshan District Shenzhen 518060 Guangdong China
| | - Danyang Chen
- Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound ImagingNational‐Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringHealth Science CenterShenzhen University No. 1066 Xueyuan Road, Nanshan District Shenzhen 518060 Guangdong China
| | - Xifeng Lu
- Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound ImagingNational‐Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringHealth Science CenterShenzhen University No. 1066 Xueyuan Road, Nanshan District Shenzhen 518060 Guangdong China
| | - Qianjun He
- Guangdong Provincial Key Laboratory of Biomedical Measurements and Ultrasound ImagingNational‐Regional Key Technology Engineering Laboratory for Medical UltrasoundSchool of Biomedical EngineeringHealth Science CenterShenzhen University No. 1066 Xueyuan Road, Nanshan District Shenzhen 518060 Guangdong China
| |
Collapse
|
8
|
Akopov G, Yeung MT, Kaner RB. Rediscovering the Crystal Chemistry of Borides. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1604506. [PMID: 28323358 DOI: 10.1002/adma.201604506] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 11/14/2016] [Indexed: 06/06/2023]
Abstract
For decades, borides have been primarily studied as crystallographic oddities. With such a wide variety of structures (a quick survey of the Inorganic Crystal Structure Database counts 1253 entries for binary boron compounds!), it is surprising that the applications of borides have been quite limited despite a great deal of fundamental research. If anything, the rich crystal chemistry found in borides could well provide the right tool for almost any application. The interplay between metals and the boron results in even more varied material's properties, many of which can be tuned via chemistry. Thus, the aim of this review is to reintroduce to the scientific community the developments in boride crystal chemistry over the past 60 years. We tie structures to material properties, and furthermore, elaborate on convenient synthetic routes toward preparing borides.
Collapse
Affiliation(s)
- Georgiy Akopov
- Department of Chemistry and Biochemistry and California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Michael T Yeung
- Department of Chemistry and Biochemistry and California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Richard B Kaner
- Department of Chemistry and Biochemistry and California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
- Department of Materials Science and Engineering and California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| |
Collapse
|
9
|
Davari Esfahani MM, Zhu Q, Dong H, Oganov AR, Wang S, Rakitin MS, Zhou XF. Novel magnesium borides and their superconductivity. Phys Chem Chem Phys 2017; 19:14486-14494. [DOI: 10.1039/c7cp00840f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
With the motivation of searching for new superconductors in the Mg–B system, we performed ab initio evolutionary searches for all the stable compounds in this binary system in the pressure range of 0–200 GPa.
Collapse
Affiliation(s)
- M. Mahdi Davari Esfahani
- Department of Geosciences
- Center for Materials by Design, and Institute for Advanced Computational Science
- State University of New York
- Stony Brook
- USA
| | - Qiang Zhu
- Department of Geosciences
- Center for Materials by Design, and Institute for Advanced Computational Science
- State University of New York
- Stony Brook
- USA
| | - Huafeng Dong
- Department of Geosciences
- Center for Materials by Design, and Institute for Advanced Computational Science
- State University of New York
- Stony Brook
- USA
| | - Artem R. Oganov
- Department of Geosciences
- Center for Materials by Design, and Institute for Advanced Computational Science
- State University of New York
- Stony Brook
- USA
| | - Shengnan Wang
- Department of Geosciences
- Center for Materials by Design, and Institute for Advanced Computational Science
- State University of New York
- Stony Brook
- USA
| | - Maksim S. Rakitin
- Department of Geosciences
- Center for Materials by Design, and Institute for Advanced Computational Science
- State University of New York
- Stony Brook
- USA
| | - Xiang-Feng Zhou
- Department of Geosciences
- Center for Materials by Design, and Institute for Advanced Computational Science
- State University of New York
- Stony Brook
- USA
| |
Collapse
|
10
|
Ilyushin GD. Symmetry and topology code of cluster self-assembly of icosahedral framework structures of boron and borides. RUSS J INORG CHEM+ 2016. [DOI: 10.1134/s0036023616140023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
11
|
Reber AC, Khanna SN. Electronic structure, stability, and oxidation of boron-magnesium clusters and cluster solids. J Chem Phys 2015; 142:054304. [PMID: 25662642 DOI: 10.1063/1.4907273] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Arthur C. Reber
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284, USA
| | - Shiv N. Khanna
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284, USA
| |
Collapse
|
12
|
Synthesis, crystal structure and properties of Mg3B36Si9C and related rare earth compounds RE3−xB36Si9C (RE=Y, Gd–Lu). J SOLID STATE CHEM 2013. [DOI: 10.1016/j.jssc.2013.05.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
13
|
Bindi L, Figini Albisetti A, Giunchi G, Malpezzi L, Masciocchi N. Redetermination of Mg(2)B(25) based on single-crystal X-ray data. Acta Crystallogr Sect E Struct Rep Online 2012; 68:i50. [PMID: 22719279 PMCID: PMC3379058 DOI: 10.1107/s1600536812023768] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 05/24/2012] [Indexed: 11/22/2022]
Abstract
The crystal structure of Mg2B25, dimagnesium pentaeicosaboride, was reexamined from single-crystal X-ray diffraction data. The structural model previously reported on the basis of powder X-ray diffraction data [Giunchi et al. (2006 ▶). Solid State Sci.8, 1202–1208] has been confirmed, although a much higher precision refinement was achieved, leading to much smaller standard uncertainties on bond lengths and refined occupancy factors. Moreover, all atoms were refined with anisotropic displacement parameters. Mg2B25 crystallizes in the β-boron structure type and is isostructural with other rhombohedral compounds of the boron-rich metal boride family. Magnesium atoms are found in interstitial sites on special positions (two with site symmetry .m, one with .2 and one with 3m), all with partial occupancies.
Collapse
|
14
|
Malik ZP, Sologub O, Grytsiv A, Giester G, Rogl PF. Crystal Structure of Novel Ni–Zn Borides: First Observation of a Boron–Metal Nested Cage Unit: B20Ni6. Inorg Chem 2011; 50:7669-75. [DOI: 10.1021/ic2007167] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zahida P. Malik
- Institute of Physical Chemistry, University of Vienna, Währingerstrasse 42, A-1090 Vienna, Austria
| | - Oksana Sologub
- Institute of Physical Chemistry, University of Vienna, Währingerstrasse 42, A-1090 Vienna, Austria
| | - Andriy Grytsiv
- Institute of Physical Chemistry, University of Vienna, Währingerstrasse 42, A-1090 Vienna, Austria
| | - Gerald Giester
- Institute of Mineralogy and Crystallography, University of Vienna, Althanstr. 14, A-1090 Vienna, Austria
| | - Peter F. Rogl
- Institute of Physical Chemistry, University of Vienna, Währingerstrasse 42, A-1090 Vienna, Austria
| |
Collapse
|