First-Principles Energetics of Some Nonmetallic Impurity Atoms in Plutonium Dioxide

ABSTRACTLocation of diffused 57Co atoms in single crystals, bicrystals and polycrystals of pure iron and Fe72Al28alloy were investigated by means of emission Mössbauer spectroscopy. To interpret the results, first principles calculations of iron atom magnetic moments and hyper-fine field were carried out. From comparison of M6ssbauer spectra of single crystals with those of bicrystals and polycrystals, an information about grain boundary positions occupied by diffusing atoms is obtained. It is shown that about 5% of the diffusing atoms at the {112} grain boundary of iron are located at the positions either having impurity atoms in the nearest neighbourhood or characterized by larger atomic spacing in comparison with the bulk. In the Fe72Al28 a dominating portion of diffusing atoms have different surrounding than in grain volume. An enrichment of grain boundaries by aluminum could explain their hyperfine parameters.

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The stability and diffusion properties of foreign impurity atoms on the surface and in the bulk of vanadium: A first-principles study

Computational Materials Science ◽

10.1016/j.commatsci.2013.08.011 ◽

2014 ◽

Vol 81 ◽

pp. 191-198 ◽

Cited By ~ 15

Author(s):

Ling Gong ◽

Qiulei Su ◽

Huiqiu Deng ◽

Shifang Xiao ◽

Wangyu Hu

Keyword(s):

First Principles ◽

Impurity Atoms ◽

First Principles Study ◽

The Stability ◽

And Diffusion ◽

Diffusion Properties

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First-Principles Calculation of Phonon and Schottky Heat Capacities of Plutonium Dioxide

Journal of the Physical Society of Japan ◽

10.7566/jpsj.84.053602 ◽

2015 ◽

Vol 84 (5) ◽

pp. 053602 ◽

Cited By ~ 3

Author(s):

Hiroki Nakamura ◽

Masahiko Machida ◽

Masato Kato

Keyword(s):

First Principles ◽

Heat Capacities ◽

First Principles Calculation ◽

Plutonium Dioxide

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Effect of Impurities on the Electronic Structureof Grain Boundaries and Intergranular Cohesionin Tungsten

MRS Proceedings ◽

10.1557/proc-291-109 ◽

1992 ◽

Vol 291 ◽

Cited By ~ 1

Author(s):

Genrich L. Krasko

Keyword(s):

First Principles ◽

High Strength ◽

Interatomic Interaction ◽

Competition Effect ◽

Impurity Atoms ◽

Intergranular Embrittlement ◽

Effect Of Impurities ◽

Site Competition ◽

Semi Empirical ◽

Segregation Of Impurities

ABSTRACTThe cohesion of a grain boundary (GB) is believed to be the controlling factor limiting theductility of high-strength metallic alloys, and particularly W. Intergranular embrittlement isusually associated with segregation of impurities at the GBs. Impurities present in ppmconcentrations can result in a dramatic decrease in plasticity. This paper reviews recent results onboth semi-empirical and first-principles modelling of the energetics and the electronic structuresof impurities on a Σ3 (111) GB in W. Our calculations have shown that impurities, such as N, O,P, S, and Si weaken the intergranular cohesion resulting in “loosening” the GB. The presence ofB and C on the contrary, enhances the interatomic interaction across the GB. The so-called site-competition effect should play an important role affecting impurity distribution in W GBs.Among the impurities analyzed, B in the GB has the lowest energy, and thus would tend todisplace other impurity atoms from the GB. Microalloying with 10-50 ppm B may be an effectiveway of improving tungsten's ductility. These results are important for understanding thefundamental physics of intergranular embrittlement.

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Structural, electronic and magnetic properties of (N, C)-codoped ZnO nanotube: First principles study

International Journal of Modern Physics C ◽

10.1142/s0129183115501302 ◽

2015 ◽

Vol 26 (11) ◽

pp. 1550130 ◽

Cited By ~ 11

Author(s):

Amirhosein Esmailian ◽

Masoud Shahrokhi ◽

Faramarz Kanjouri

Keyword(s):

Magnetic Properties ◽

First Principles ◽

Density Functional ◽

Nearest Neighbor ◽

First Principle ◽

Functional Theory ◽

Impurity Atoms ◽

Zno Nanotube ◽

The Density Functional Theory ◽

Zno Nanotubes

We have studied the electronic structure and magnetic properties of Nitrogen and Carbon codoped ZnO (5,0) single-walled zigzag nanotube using first-principle calculations based on the density functional theory. We performed our calculations for N - and C - codoping ZnO nanotube in two different configurations. For the first configuration in which the two impurity atoms ( N or C ) are on first nearest-neighbor sites in the plane of codoping, our calculation predicts that the N - and C -codoped ZnO nanotubes are antiferromagnetic material with no net magnetization. On the other hand, it is found that for the configuration in which the two impurity atoms are next nearest-neighbors, a spin polarization results in a magnetic moment in the N - and C -codoped ZnO nanotubes.

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A first-principles study on the bond characteristics in carbon containing Mo, Ag, or Al impurity atoms

Carbon ◽

10.1016/j.carbon.2007.11.005 ◽

2008 ◽

Vol 46 (2) ◽

pp. 185-188 ◽

Cited By ~ 19

Author(s):

Jung-Hae Choi ◽

Seung-Cheol Lee ◽

Kwang-Ryeol Lee

Keyword(s):

First Principles ◽

Impurity Atoms ◽

First Principles Study ◽

Bond Characteristics

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Systematic Investigation of Gettering Effects on 4th Row Element Impurities in Si by Dopant Atoms

Advances in Materials Science and Engineering ◽

10.1155/2009/309209 ◽

2009 ◽

Vol 2009 ◽

pp. 1-3 ◽

Cited By ~ 3

Author(s):

Koji Sueoka ◽

Ken Kamimura ◽

Seiji Shiba

Keyword(s):

Binding Energy ◽

Transition Metals ◽

Diffusion Barrier ◽

First Principles ◽

Systematic Investigation ◽

First Principles Calculation ◽

Light Elements ◽

Impurity Atoms ◽

Dopant Atoms ◽

P Type

The gettering of 4th row element impurities (K, Ca, 3d transition metals, and Zn) in Si crystals by dopant atoms was systematically investigated by first-principles calculation through evaluation of the diffusion barrier and the binding energy. The dopant atoms considered include p-type dopants (B), n-type dopants (P, As, Sb), or light elements (C, O). It was found that (1) the diffusion barrier of impurity atoms decreases with an increase in their atomic number up to Ni, (2) B atom becomes an efficient gettering center for metals except for Ni, (3) most of the metals except for Fe and Co cannot be gettered by n-type dopants, and (4) C and O atoms alone do not become efficient gettering centers for the metals used in actual LSI processes. The vacancy and n-type dopant complexes (P, As, Sb) can be efficient gettering centers for Cu in n/n+ epitaxial wafers.

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Intrinsic defects and krypton impurity atoms in hcp titanium: A first-principles study

Physical Review B ◽

10.1103/physrevb.83.054120 ◽

2011 ◽

Vol 83 (5) ◽

Cited By ~ 9

Author(s):

Abdulrafiu T. Raji ◽

Riccardo Mazzarello ◽

Sandro Scandolo ◽

Schadrack Nsengiyumva ◽

Margit Härting ◽

...

Keyword(s):

First Principles ◽

Intrinsic Defects ◽

Impurity Atoms ◽

First Principles Study

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Improvement of the arsine adsorption by doping on monolayer MoS2

Functional Materials Letters ◽

10.1142/s1793604719500589 ◽

2019 ◽

Vol 12 (04) ◽

pp. 1950058 ◽

Cited By ~ 1

Author(s):

Gongjie Xu ◽

Gongming Song ◽

Yaole Wang

Keyword(s):

Charge Transfer ◽

Adsorption Energy ◽

First Principles ◽

Effective Charge ◽

Type System ◽

First Principles Calculation ◽

Monolayer Mos2 ◽

Text Type ◽

Impurity Atoms ◽

Effective Charge Transfer

The improvement of the arsine adsorption on monolayer MoS2 by doping has been investigated by first-principles calculation. The impurity atoms Si, P, and Cl, have been introduced to substitute S atoms to form an [Formula: see text]- or [Formula: see text]-type system. The electronic properties of MoS2 with dopants P and Cl are insensitive to the adsorption of AsH3. The Si-MoS2 with adsorbed AsH3 configuration has the largest adsorption energy, the lowest adsorbed height, and the most effective charge transfer. It is indicated that the properties of MoS2 can be improved by doping for detecting AsH3 molecules.

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