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Wagner FR. Delocalization-ratio analysis of 3-center bonding in position-space for closo-boranes and related systems: Approaching the styx picture and beyond. J Comput Chem 2024. [PMID: 39211997 DOI: 10.1002/jcc.27486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 07/31/2024] [Accepted: 08/06/2024] [Indexed: 09/04/2024]
Abstract
Closo-boron hydrides BnHn 2- (n = 5-12) are a conceptually well understood class of compounds. For these and a few related prototype compounds, both the local and the global picture of 3-center bonding are extracted from position-space quantities based on the electron density and the pair density. For this purpose, three-center delocalization indices between quantum theory of atoms in molecules (QTAIM) atoms in position space are used to develop a consistent set of local bond and triangle, and global cluster delocalization ratios (DRs), which are quantitatively compared with conceptual Γ values derived from the styx code for each cluster. Combination of the cluster DRs with associated effective numbers of skeletal electron sharing (SES) for selected cluster surface edges, triangles, or the whole cluster yields effective styx type values describing the trend and even the size of the conceptual styx codes for closo-boranes BnHn 2- and related systems with increasing cluster size n reasonably well. For nonuniform cluster topologies, the different vertex degrees are shown to cause systematic 3-center wise bond delocalization effects for the associated edges and triangles of different average vertex degrees. Extension of DR analysis beyond the styx type triangular cluster-surface bonding corresponds to a triangulation of multicentric bonding. The cluster-wise results keep indicating consistency with the mixed 2- and 3-center bonding approach. The successfully established chemical meaning of the local edge, triangle, and global cluster DRs and their associated SES values constitutes the basis for systematic investigations of mixed 2- and 3-center bonding scenarios in particular in intermetallic and related (endohedral) cluster compounds in the future.
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Affiliation(s)
- Frank R Wagner
- Chemical Metals Science, Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
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2
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Ahmed M, Akram MA, Bano A, Khan MZ, Rehman R, Jan R, Javed S. A key parametric study of ultrasonic exfoliation of 2D TiB 2 using DI water as a unique medium. Heliyon 2024; 10:e29417. [PMID: 38665571 PMCID: PMC11043946 DOI: 10.1016/j.heliyon.2024.e29417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/25/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024] Open
Abstract
Liquid Phase Exfoliation (LPE) is a very effective technique for the synthesis of few layered two dimensional (2D) nanosheets. There is a surge to find environment friendly solvents for efficient exfoliation of layered materials to produce 2D nanosheets. TiB2 is an important layered material with very little reported work on its 2D nanosheets. The present work is about successful LPE of TiB2 using deionized (DI) water as a clean, green and low cost dispersion medium to make TiB2 nanosheets. The impact of ultrasonication conditions i.e. input power and treatment duration for efficient synthesis of few layered 2D nanosheets in DI water is studied by Atomic Force Microscopy (AFM), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). It is found that by increasing input power, the layer thickness is reduced from bulk to 34 nm with lateral dimensions as huge as up to 5 μm. The increased treatment duration has further reduced the layer thickness to 21 nm associated with a decrease in lateral dimensions to about 1 μm. The mechanism of variation in the aspect ratio of the 2D nanosheets with ultrasonication power and treatment duration is explained. The optimum conditions for the fabrication of high aspect ratio 2D nanosheets of TiB2 owe to a greater acoustic cavitation intensity, an optimum treatment duration and a homogenous distribution of the cavitation events while using an appropriate size of the sonotrode in the sonicated volume during ultrasonication.
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Affiliation(s)
- Marghoob Ahmed
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
| | - Muhammad Aftab Akram
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
- Department of Materials Science and Engineering, Pak-Austria Fachhochschule Institute of Applied Sciences and Technology, Mang Haripur, 22620, Khyber Pakhtunkhwa, Pakistan
| | - Afsar Bano
- Department of Physics, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences, LUMS, 54792, Lahore, Pakistan
| | - Muhammad Zafar Khan
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
| | - Rafia Rehman
- Section of Phytochemistry and Natural Products, Department of Biological Sciences, National University of Medical Sciences, Rawalpindi, 46000, Punjab, Pakistan
| | - Rahim Jan
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
| | - Sofia Javed
- Department of Materials Engineering, School of Chemical & Materials Engineering, National University of Sciences & Technology, Islamabad, 44000, Pakistan
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3
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Palem RR, Bathula C, Shimoga G, Lee SH, Ghfar AA, Sekar S, Kim HS, Seo YS, Rabani I. Fabrication of Ru loaded MgB 2 with guar gum hybrid for photocatalytic degradation of crystal violet. Int J Biol Macromol 2023; 253:126948. [PMID: 37722634 DOI: 10.1016/j.ijbiomac.2023.126948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 09/04/2023] [Accepted: 09/08/2023] [Indexed: 09/20/2023]
Abstract
Today, dyes/pigment-based materials are confronting a serious issue in harming marine ecology. Annihilate these serious water pollutants using photoactive 2D nanohybrid catalysts showed promising comparativeness over available photocatalysts. In the present work, a facile route to decorate Ruthenium (Ru) on 2D MgB2 flower-like nanostructures was developed via ecofriendly guar gum biopolymer substantial template (MgB2/GG@Ru NFS) and its photocatalytic performance was reported. Synthesis of MgB2@Ru, MgB2/GG@Ru NFS and commercial MgB2, was studied by FTIR, XRD, FE-SEM, EDX, AFM, TEM, UV-vis spectra, and XPS analysis. From the results, the MgB2/GG@Ru NFS exhibited a superior photocatalytic performance (99.7 %) than its precursors MgB2@Ru (79.7 %), and MgB2 (53.7 %), with the degradation efficiency of the crystal violet (CV) within 100 min under visible light irradiation. The proposed photo-catalyst MgB2/GG@Ru NFS showed negligible loss of photocatalytic activity even after five successive cycles, revealing its reusability and enhanced stability due to the network structure. The photocatalytic mechanism for MgB2/GG@Ru NFS was evaluated by trapping experiment of active species, verifying that superoxide (O2-) and electron (e-) contributed significant role in the dye degradation.
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Affiliation(s)
- Ramasubba Reddy Palem
- Department of Medical Biotechnology, Dongguk University, 32 Dongguk-ro, Ilsandong-gu, Goyang, Gyeonggi 10326, Republic of Korea
| | - Chinna Bathula
- Division of Electronics and Electrical Engineering, Dongguk University-Seoul, Seoul 04620, Republic of Korea
| | - Ganesh Shimoga
- Department of Biotechnology and Nanomedicine, SINTEF Industry, 7034 Trondheim, Norway; Interaction Lab, Future Convergence Engineering, Advanced Technology Research Centre, Korea University of Technology and Education, Cheonan-si 31253, Chungcheongnam-do, Republic of Korea
| | - Soo-Hong Lee
- Department of Medical Biotechnology, Dongguk University, 32 Dongguk-ro, Ilsandong-gu, Goyang, Gyeonggi 10326, Republic of Korea
| | - Ayman A Ghfar
- Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Sankar Sekar
- Quantum-functional Semiconductor Research Center, Dongguk University-Seoul, Seoul 04620, Republic of Korea; Division of Physics and Semiconductor Science, Dongguk University-Seoul, Seoul 04620, Republic of Korea
| | - Hyun-Seok Kim
- Division of Electronics and Electrical Engineering, Dongguk University-Seoul, Seoul 04620, Republic of Korea
| | - Young-Soo Seo
- Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea
| | - Iqra Rabani
- Department of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Republic of Korea.
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Shteingolts SA, Stash AI, Tsirelson VG, Fayzullin RR. Real-Space Interpretation of Interatomic Charge Transfer and Electron Exchange Effects by Combining Static and Kinetic Potentials and Associated Vector Fields. Chemistry 2022; 28:e202200985. [PMID: 35638164 DOI: 10.1002/chem.202200985] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Indexed: 11/09/2022]
Abstract
Intricate behaviour of one-electron potentials from the Euler equation for electron density and corresponding gradient force fields in crystals was studied. Channels of locally enhanced kinetic potential and corresponding saddle Lagrange points were found between chemically bonded atoms. Superposition of electrostatic ϕ e s r and kinetic ϕ k r potentials and electron density ρ r allowed partitioning any molecules and crystals into atomic ρ - and potential-based ϕ -basins; ϕ k -basins explicitly account for the electron exchange effect, which is missed for ϕ e s -ones. Phenomena of interatomic charge transfer and related electron exchange were explained in terms of space gaps between zero-flux surfaces of ρ - and ϕ -basins. The gap between ϕ e s - and ρ -basins represents the charge transfer, while the gap between ϕ k - and ρ -basins is a real-space manifestation of sharing the transferred electrons caused by the static exchange and kinetic effects as a response against the electron transfer. The regularity describing relative positions of ρ -, ϕ e s -, and ϕ k - basin boundaries between interacting atoms was proposed. The position of ϕ k -boundary between ϕ e s - and ρ -ones within an electron occupier atom determines the extent of transferred electron sharing. The stronger an H⋅⋅⋅O hydrogen bond is, the deeper hydrogen atom's ϕ k -basin penetrates oxygen atom's ρ -basin, while for covalent bonds a ϕ k -boundary closely approaches a ϕ e s -one indicating almost complete sharing of the transferred electrons. In the case of ionic bonds, the same region corresponds to electron pairing within the ρ -basin of an electron occupier atom.
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Affiliation(s)
- Sergey A Shteingolts
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, Kazan, 420088, Russian Federation
| | - Adam I Stash
- A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 28 Vavilov Street, Moscow, 119991, Russian Federation
| | - Vladimir G Tsirelson
- D.I. Mendeleev University of Chemical Technology, 9 Miusskaya Square, Moscow, 125047, Russian Federation.,South Ural State University, 76 Lenin Avenue, Chelyabinsk, 454080, Russian Federation
| | - Robert R Fayzullin
- Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, 8 Arbuzov Street, Kazan, 420088, Russian Federation
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Zhang Z, Zhu S, Liu Y, Liu L, Ma Z. Enthalpy driving force and chemical bond weakening: the solid-solution formation mechanism and densification behavior of high-entropy diborides (Hf1-x/4Zr1-x/4Nb1-x/4Ta1-x/4Scx)B2. Ann Ital Chir 2022. [DOI: 10.1016/j.jeurceramsoc.2022.03.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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6
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Menéndez Crespo D, Wagner FR, Francisco E, Martín Pendás Á, Grin Y, Kohout M. Interacting Quantum Atoms Method for Crystalline Solids. J Phys Chem A 2021; 125:9011-9025. [PMID: 34596415 PMCID: PMC8521528 DOI: 10.1021/acs.jpca.1c06574] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
An implementation
of the Interacting Quantum Atoms method for crystals
is presented. It provides a real space energy decomposition of the
energy of crystals in which all energy components are physically meaningful.
The new package ChemInt enables one to compute intra-atomic and inter-atomic
energies, as well as electron population measures used for quantitative
description of chemical bonds in crystals. The implementation is tested
and applied to characteristic molecular and crystalline systems with
different types of bonding.
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Affiliation(s)
| | | | - Evelio Francisco
- Departamento de Química Física y Analítica, University of Oviedo, 33006 Oviedo, Spain
| | - Ángel Martín Pendás
- Departamento de Química Física y Analítica, University of Oviedo, 33006 Oviedo, Spain
| | - Yuri Grin
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
| | - Miroslav Kohout
- Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany
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7
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James AL, Lenka M, Pandey N, Ojha A, Kumar A, Saraswat R, Thareja P, Krishnan V, Jasuja K. Processable dispersions of photocatalytically active nanosheets derived from titanium diboride: self assembly into hydrogels and paper-like macrostructures. NANOSCALE 2020; 12:17121-17131. [PMID: 32785411 DOI: 10.1039/d0nr03677c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Titanium diboride (TiB2), a layered ceramic material, is well-known for its ultrahigh strength, wear resistance, and chemical inertness. In this work, we present a simple one-pot chemical approach that yields sheet-like nanostructures from TiB2. We serendipitously found that TiB2 crystals can undergo complete dissolution in a mild aqueous solution of H2O2 under ambient conditions. This unexpected dissolution of TiB2 is followed by non-classical recrystallization that results in nanostructures with sheet-like morphology exhibiting Ti-O and B-O functional groups. We show that this pathway can be used to obtain an aqueous dispersion of nanosheets with concentrations ≥3 mg mL-1. Interestingly, these nanosheets tend to transform into a hydrogel without the need of any additives. We found that the degree of gelation depends on the ratio of TiB2 to H2O2, which can be tuned to achieve gels with a shear modulus of 0.35 kPa. We also show this aqueous dispersion of nanosheets is processable and forms hierarchical paper-like macrostructures upon vacuum filtration. Such an ability to assemble into free-standing 3D structures would enable a leap to practical applications. We also show that the high surface area and presence of oxy-functional groups on these nanosheets endow them a superior photocatalytic activity to degrade organic pollutants. This exemplifies the rich potential that TiB2 offers upon nanoscaling. The results presented here not only add a novel material to the 2D flatland but also urge the scientific community to revisit the chemistry of metal borides, that have been traditionally considered as relatively inert ceramics.
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Affiliation(s)
- Asha Liza James
- Discipline of Chemical Engineering, Indian Institute of Technology Gandhinagar, Palaj, Gujarat 382355, India.
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8
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Thermoelectric and magnetic properties of rare earth borides: Boron cluster and layered compounds. J SOLID STATE CHEM 2019. [DOI: 10.1016/j.jssc.2019.03.046] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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9
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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] [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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10
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11
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Pecher L, Laref S, Raupach M, Tonner R. Ether auf Si(001): Ein Paradebeispiel für die Gemeinsamkeiten zwischen Oberflächenwissenschaften und organischer Molekülchemie. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201707428] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lisa Pecher
- Fachbereich Chemie und WZMW; Philipps-Universität Marburg; Hans-Meerwein-Str. 4 35032 Marburg Deutschland
| | - Slimane Laref
- Fachbereich Chemie und WZMW; Philipps-Universität Marburg; Hans-Meerwein-Str. 4 35032 Marburg Deutschland
- King Abdullah University of Science and Technology (KAUST); Physical Science and Engineering Division (PSE); Thuwal 23955 Saudi Arabien
| | - Marc Raupach
- Fachbereich Chemie und WZMW; Philipps-Universität Marburg; Hans-Meerwein-Str. 4 35032 Marburg Deutschland
| | - Ralf Tonner
- Fachbereich Chemie und WZMW; Philipps-Universität Marburg; Hans-Meerwein-Str. 4 35032 Marburg Deutschland
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12
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Pecher L, Laref S, Raupach M, Tonner R. Ethers on Si(001): A Prime Example for the Common Ground between Surface Science and Molecular Organic Chemistry. Angew Chem Int Ed Engl 2017; 56:15150-15154. [DOI: 10.1002/anie.201707428] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Lisa Pecher
- Faculty of Chemistry and Material Sciences Center; Philipps-Universität Marburg; Hans-Meerwein-Strasse 4 35032 Marburg Germany
| | - Slimane Laref
- Faculty of Chemistry and Material Sciences Center; Philipps-Universität Marburg; Hans-Meerwein-Strasse 4 35032 Marburg Germany
- Current address: King Abdullah University of Science and Technology (KAUST); Physical Science and Engineering Division (PSE); Thuwal 23955 Saudi Arabia
| | - Marc Raupach
- Faculty of Chemistry and Material Sciences Center; Philipps-Universität Marburg; Hans-Meerwein-Strasse 4 35032 Marburg Germany
| | - Ralf Tonner
- Faculty of Chemistry and Material Sciences Center; Philipps-Universität Marburg; Hans-Meerwein-Strasse 4 35032 Marburg Germany
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Golub P, Baranov AI. Domain overlap matrices from plane-wave-based methods of electronic structure calculation. J Chem Phys 2017; 145:154107. [PMID: 27782480 DOI: 10.1063/1.4964760] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Plane waves are one of the most popular and efficient basis sets for electronic structure calculations of solids; however, their delocalized nature makes it difficult to employ for them classical orbital-based methods of chemical bonding analysis. The quantum chemical topology approach, introducing chemical concepts via partitioning of real space into chemically meaningful domains, has no difficulties with plane-wave-based basis sets. Many popular tools employed within this approach, for instance delocalization indices, need overlap integrals over these domains-the elements of the so called domain overlap matrices. This article reports an efficient algorithm for evaluation of domain overlap matrix elements for plane-wave-based calculations as well as evaluation of its implementation for one of the most popular projector augmented wave (PAW) methods on the small set of simple and complex solids. The stability of the obtained results with respect to PAW calculation parameters has been investigated, and the comparison of the results with the results from other calculation methods has also been made.
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Affiliation(s)
- Pavlo Golub
- Department of Chemistry and Food Chemistry, Technical University of Dresden, Bergstrasse 66, 01062 Dresden, Germany
| | - Alexey I Baranov
- Department of Chemistry and Food Chemistry, Technical University of Dresden, Bergstrasse 66, 01062 Dresden, Germany
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14
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James AL, Jasuja K. Chelation assisted exfoliation of layered borides towards synthesizing boron based nanosheets. RSC Adv 2017. [DOI: 10.1039/c6ra26658d] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Selective extraction of inter-layer metal atoms by the chelating agent delaminates layered metal borides into boron based nanosheets.
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Affiliation(s)
- Asha Liza James
- Discipline of Chemical Engineering
- Indian Institute of Technology Gandhinagar
- India
| | - Kabeer Jasuja
- Discipline of Chemical Engineering
- Indian Institute of Technology Gandhinagar
- India
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Lassoued S, Boucher B, Boutarfaia A, Gautier R, Halet JF. The coloring problem in the solid-state metal boride carbide ScB2C2: a theoretical analysis. ZEITSCHRIFT FUR NATURFORSCHUNG SECTION B-A JOURNAL OF CHEMICAL SCIENCES 2016. [DOI: 10.1515/znb-2016-0056] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The electronic properties of the layered ternary metal boride carbide ScB2C2, the structure of which consists of B/C layers made of fused five- and seven-membered rings alternating with scandium sheets, are analyzed. In particular, the respective positions of the B and C atoms (the so-called coloring problem) are tackled using density functional theory, quantum theory of atoms in molecules, and electron localizability indicator calculations. Results reveal that (i) the most stable coloring minimizes the number of B–B and C–C contacts and maximizes the number of boron atoms in the heptagons, (ii) the compound is metallic in character, and (iii) rather important covalent bonding occurs between the metallic sheets and the boron–carbon network.
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Affiliation(s)
| | | | - Ahmed Boutarfaia
- Faculté des Mathématiques et des Sciences de la Matière, Université Kasdi Merbah-Ouargla , Ouargla, Algeria
| | - Régis Gautier
- Institut des Sciences Chimiques de Rennes , UMR 6226 CNRS, Ecole Nationale Supérieure de Chimie de Rennes, Université de Rennes 1 , F-35042 Rennes, France
| | - Jean-François Halet
- Institut des Sciences Chimiques de Rennes , UMR 6226 CNRS, Ecole Nationale Supérieure de Chimie de Rennes, Université de Rennes 1 , F-35042 Rennes, France
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16
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Terlan B, Akselrud L, Baranov AI, Borrmann H, Grin Y. On the transferability of electron density in binary vanadium borides VB, V3B4 and VB2. ACTA CRYSTALLOGRAPHICA SECTION B, STRUCTURAL SCIENCE, CRYSTAL ENGINEERING AND MATERIALS 2015; 71:777-787. [PMID: 26634735 DOI: 10.1107/s2052520615018363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 09/30/2015] [Indexed: 06/05/2023]
Abstract
Binary vanadium borides are suitable model systems for a systematic analysis of the transferability concept in intermetallic compounds due to chemical intergrowth in their crystal structures. In order to underline this structural relationship, topological properties of the electron density in VB, V3B4 and VB2 reconstructed from high-resolution single-crystal X-ray diffraction data as well as derived from quantum chemical calculations, are analysed in terms of Bader's Quantum Theory of Atoms in Molecules [Bader (1990). Atoms in Molecules: A Quantum Theory, 1st ed. Oxford: Clarendon Press]. The compounds VB, V3B4 and VB2 are characterized by a charge transfer from the metal to boron together with two predominant atomic interactions, the shared covalent B-B interactions and the polar covalent B-M interactions. The resembling features of the crystal structures are well reflected by the respective B-B interatomic distances as well as by ρ(r) values at the B-B bond critical points. The latter decrease with an increase in the corresponding interatomic distances. The B-B bonds show transferable electron density properties at bond critical points depending on the respective bond distances.
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Affiliation(s)
- Bürgehan Terlan
- Physical Chemistry, TU Dresden, Bergstrasse 66b, 01062 Dresden, Germany
| | - Lev Akselrud
- Max-Planck Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Alexey I Baranov
- Max-Planck Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Horst Borrmann
- Max-Planck Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
| | - Yuri Grin
- Max-Planck Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
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Zheng Q, Gumeniuk R, Rosner H, Schnelle W, Prots Y, Burkhardt U, Grin Y, Leithe-Jasper A. Synthesis, crystal structure and properties of the new superconductors TaRuB and NbOsB. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:415701. [PMID: 26418029 DOI: 10.1088/0953-8984/27/41/415701] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Two new ternary compounds TaRuB and NbOsB were synthesized by arc-melting and annealing at 1500-1850 °C. They crystallize in orthorhombic primitive structures with space group Pbam. Magnetic susceptibility, electrical resistivity, and specific heat measurements reveal bulk superconductivity for metallic TaRuB with a T(c) ≈ 4 K. Electronic structure calculations by DFT methods show that 4d and 5d transition-metal states dominate the density of states (DOS) at the Fermi level E(F) with a pronounced quasi one-dimensional behaviour along the [0 0 1] direction. Comparison of the calculated DOS at E(F) with specific heat data reveals a moderate electron-phonon coupling. Possible small boron vacancies could significantly reduce the DOS at E(F), hence decrease T(c) for samples annealed at higher temperatures. For NbOsB, the DOS(E(F)) is strongly reduced due to an increase of covalent bonding interactions between Os and B. Accordingly, a lower T(c) ≈ 1 K is observed.
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Affiliation(s)
- Qiang Zheng
- Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Straße 40, 01187 Dresden, Germany
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Alling B, Högberg H, Armiento R, Rosen J, Hultman L. A theoretical investigation of mixing thermodynamics, age-hardening potential, and electronic structure of ternary M(1)1-x M(2)xB2 alloys with AlB2 type structure. Sci Rep 2015; 5:9888. [PMID: 25970763 PMCID: PMC4429488 DOI: 10.1038/srep09888] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 03/19/2015] [Indexed: 11/24/2022] Open
Abstract
Transition metal diborides are ceramic materials with potential applications as hard protective thin films and electrical contact materials. We investigate the possibility to obtain age hardening through isostructural clustering, including spinodal decomposition, or ordering-induced precipitation in ternary diboride alloys. By means of first-principles mixing thermodynamics calculations, 45 ternary M11–xM2xB2 alloys comprising MiB2 (Mi = Mg, Al, Sc, Y, Ti, Zr, Hf, V, Nb, Ta) with AlB2 type structure are studied. In particular Al1–xTixB2 is found to be of interest for coherent isostructural decomposition with a strong driving force for phase separation, while having almost concentration independent a and c lattice parameters. The results are explained by revealing the nature of the electronic structure in these alloys, and in particular, the origin of the pseudogap at EF in TiB2, ZrB2, and HfB2.
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Affiliation(s)
- B Alling
- Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
| | - H Högberg
- Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
| | - R Armiento
- Theoretical Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
| | - J Rosen
- Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
| | - L Hultman
- Thin Film Physics, Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
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Yubuta K, Mori T, Leithe-Jasper A, Borrmann H, Grin Y, Okada S, Shishido T. Intergrowth structure of α-phase in β-type TmAlB4 compound studied by high-angle annular detector dark-field scanning transmission electron microscopy. J SOLID STATE CHEM 2014. [DOI: 10.1016/j.jssc.2014.07.038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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