Electronic structures of the tungsten borides WB, W2B and W2B5

We have investigated the electronic structures and chemical bonding of four tungsten borides, including two WB2 compounds with different crystal structures, α-W2B5 and ε-WB2.5, by ab initio calculations based on density function theory (DFT). The calculated density of state (DOS) shows that all compounds are metallic. The DOS at Fermi level is mainly contributed from 5d states of W atoms. The strong covalent bonds of boron atoms make these compounds stable. Due to a lack of electrons in boron sublattices, weak ionic bonds are generated. The charge density distributions indicate the solid B layers or B polyhedrons are interleaved by the W layers.

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Multiple crystal phases of intermetallic tungsten borides and phase-dependent electrocatalytic property for hydrogen evolution

Chemical Communications ◽

10.1039/d0cc06072k ◽

2020 ◽

Vol 56 (90) ◽

pp. 13983-13986

Author(s):

Qiuju Li ◽

Lina Wang ◽

Xuan Ai ◽

Hui Chen ◽

Jiayun Zou ◽

...

Keyword(s):

Hydrogen Evolution ◽

Electronic Structures ◽

Electrocatalytic Property ◽

Crystal Phases ◽

Tungsten Borides

Four crystal phases of intermetallic tungsten borides, including W2B, WB, WB2 and WB3, were selectively synthesized, and their crystal and electronic structures, as well as activity trend to HER, were studied.

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The Nature of Oxide Surfaces: Topographic and Electronic Structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100150666 ◽

1993 ◽

Vol 51 ◽

pp. 966-967

Author(s):

Dawn A. Bonnell ◽

Yong Liang

Keyword(s):

Transition Metal Oxides ◽

Electronic Structures ◽

Recent Progress ◽

Spatial Localization ◽

Level Of Detail ◽

Scanning Tunneling ◽

Oxide Surfaces ◽

Tunneling Microscopy ◽

Considerable Effort ◽

Complete Understanding

Recent progress in the application of scanning tunneling microscopy (STM) and tunneling spectroscopy (STS) to oxide surfaces has allowed issues of image formation mechanism and spatial resolution limitations to be addressed. As the STM analyses of oxide surfaces continues, it is becoming clear that the geometric and electronic structures of these surfaces are intrinsically complex. Since STM requires conductivity, the oxides in question are transition metal oxides that accommodate aliovalent dopants or nonstoichiometry to produce mobile carriers. To date, considerable effort has been directed toward probing the structures and reactivities of ZnO polar and nonpolar surfaces, TiO2 (110) and (001) surfaces and the SrTiO3 (001) surface, with a view towards integrating these results with the vast amount of previous surface analysis (LEED and photoemission) to build a more complete understanding of these surfaces. However, the spatial localization of the STM/STS provides a level of detail that leads to conclusions somewhat different from those made earlier.

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Paramagnetic NMR Spectroscopy as a Tool for Studying the Electronic Structures of Lanthanide and Transition Metal Complexes

INEOS OPEN ◽

10.32931/io1922r ◽

2020 ◽

Vol 2 (5) ◽

pp. 153-162

Author(s):

A. A. Pavlov ◽

Keyword(s):

Nmr Spectroscopy ◽

Transition Metal ◽

Metal Complexes ◽

Transition Metal Complexes ◽

Electronic Structures ◽

Paramagnetic Nmr

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Crystal, molecular, and electronic structures and spectroscopic characteristics of 3-[3,3-dimethyl-1,2,3,4-tetrahydroisoquinolin-1-idene]-2-pyruvic acid N-hydroxyamide

Журнал структурной химии ◽

10.26902/jsc_id40725 ◽

2019 ◽

Vol 60 (9) ◽

Keyword(s):

Pyruvic Acid ◽

Electronic Structures ◽

Spectroscopic Characteristics

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Advanced Electronic Structures

10.21236/ada258401 ◽

1992 ◽

Author(s):

Mark van Schilfgaarde

Keyword(s):

Electronic Structures

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On the Structure of Lead(II) Complexes in Aqueous Solutions. I. Trinuclear Clusters

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19950527 ◽

1995 ◽

Vol 60 (4) ◽

pp. 527-536 ◽

Cited By ~ 10

Author(s):

Martin Breza ◽

Alena Manová

Keyword(s):

Quantum Chemistry ◽

Aqueous Solutions ◽

Electronic Structures ◽

Mndo Method ◽

Model Systems ◽

Trinuclear Clusters ◽

The Stability ◽

Semiempirical Mndo

Using semiempirical MNDO method of quantum chemistry the optimal geometries and corresponding electronic structures of [Pb3(OH)n]6-n model systems as well as of their hydrated [Pb3(OH)n(H2O)8-n]6-n analogues (n = 4, 5) are investigated. The most stable trinuclear lead(II) complexes present in aqueous solutions correspond to cyclo-(μ3-OH)(μ2-OH)3Pb32+, Pb(μ-OH)2Pb(μ-OH)2Pb2+, cyclo-(μ3-OH)2(μ2-OH)3Pb3+, Pb(OH)(μ-OH)2Pb(μ-OH)Pb(OH)+ and Pb(OH)(μ-OH)2Pb(μ-OH)2Pb+ systems. The key role of OH bridges (by vanishing direct Pb-Pb bonds) on the stability of individual isomers is discussed.

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