The Electronic Structure pf Σ5 Grain Boundaries in CU

ABSTRACTWe present first-principles calculations of the densities of states (DOS's) of unrelaxed and relaxed twist and tilt grain boundaries (GB's) in Cu. The relaxed configurations were obtained through the use of the Embedded Atom Method (EAM), while the DOS's were calculated using the real-space multiplescattering theory (RSMST) approach recently introduced in the literature. The DOS's of GB's are compared against those of bulk materials as well as against one another. Although the RSMST calculations are still not self-consistent, these comparisons allow us to verify certain expected trends in the DOS's, and to verify the usefulness and reliability of our method.

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The Electronic Structure of Grain Boundaries in NB

MRS Proceedings ◽

10.1557/proc-209-131 ◽

1990 ◽

Vol 209 ◽

Author(s):

Erik C. Sowa ◽

A. Gonis ◽

X. -G. Zhang

Keyword(s):

Electronic Structure ◽

Grain Boundary ◽

Grain Boundaries ◽

Multiple Scattering ◽

First Principles ◽

Scattering Theory ◽

Real Space ◽

First Principles Calculations ◽

Densities Of States ◽

Local Densities

ABSTRACTWe present first-principles calculations of the electronic structure of Nb grain boundaries. These are the first such calculations for a bcc metal using the real-space multiple-scattering theory (RSMST). Local densities of states near a Σ5 twist grain boundary are compared to those for bulk Nb.

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First-principles Study of the Electronic Structure and Local Moment Interactions in PuAm Alloy

MRS Proceedings ◽

10.1557/proc-1104-nn02-08 ◽

2008 ◽

Vol 1104 ◽

Author(s):

Myung Joon Han ◽

Xiangang Wan ◽

Sergej Y Savrasov

Keyword(s):

Electronic Structure ◽

First Principles ◽

Local Density ◽

Exchange Interactions ◽

Kondo Lattice ◽

First Principles Calculations ◽

Correlation Effects ◽

Self Consistent ◽

5F Electrons ◽

Zero Moment

AbstractExpected to provide a clue about the origin of zero moment in the bulk phase of Plutonium, Pu1-xAmx alloys have attracted a great attention, in which upon doping the system transforms from the Kondo lattice to the diluted impurity limit. To understand the electronic structure and the magnetic properties of Pu in different crystal environments, we performed fully self-consistent first-principles calculations of the PuAm system based on the local density approximation (LDA) combined with static (LDA+U) and dynamic corrections (LDA+DMFT) for on-site electron correlations. The electronic structure strongly depends on the level of approximation for correlation effects. The exchange interactions between Pu 5f electrons and the Kondo screening strength were estimated and compared, which provide a new insight to Pu magnetism.

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Prediction of Energies of Tilt Boundaries in Al-Pb Alloy

MRS Proceedings ◽

10.1557/proc-1056-hh01-10 ◽

2007 ◽

Vol 1056 ◽

Author(s):

Y. Purohit ◽

D. L. Irving ◽

R. O. Scattergood ◽

D. W. Brenner

Keyword(s):

Grain Boundaries ◽

First Principles ◽

Density Functional ◽

First Principles Calculations ◽

Pure System ◽

Embedded Atom ◽

Unit Model ◽

Tilt Boundaries ◽

Embedded Atom Method Potential ◽

Analytic Potential

ABSTRACTEnergies for symmetric tilt grain boundaries in pure Al and in Al with substitutional Pb defects at coincident sites along the grain boundaries were calculated using a modified embedded atom method potential and density functional theory. The agreement between the analytic potential, the first principles calculations and experiment is reasonably good for the pure system. For the Al-Pb system both the analytic potential and first principles calculations predict that Pb segregation to the interface is energetically preferred compared to the dilute solution. The application of a disclination structural unit model to calculating grain boundary energies over the entire range of tilt angles is also explained.

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FIRST-PRINCIPLES CALCULATIONS OF THE ELECTRONIC STRUCTURE OF GRAIN BOUNDARIES

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1990153 ◽

1990 ◽

Vol 51 (C1) ◽

pp. C1-335-C1-340

Author(s):

E. C. SOWA ◽

A. GONIS ◽

X.-G. ZHANG

Keyword(s):

Electronic Structure ◽

Grain Boundaries ◽

First Principles ◽

First Principles Calculations

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Chen's Lattice Inversion Embedded-Atom Method for FCC Metal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.320.415 ◽

2011 ◽

Vol 320 ◽

pp. 415-420 ◽

Cited By ~ 7

Author(s):

Chuan Hui Zhang ◽

Jia Jia Han ◽

Shuo Huang ◽

Jiang Shen

Keyword(s):

First Principles ◽

Cohesive Energy ◽

Pair Potential ◽

Embedded Atom Method ◽

First Principles Calculations ◽

Embedded Atom ◽

New Type ◽

Atomic Electron Density ◽

Eam Potential ◽

Fcc Metal

We explored a new type EAM potential (CLI-EAM) that the value of atomic electron density and pair potential functions are obtained by Chen’s lattice inversion based on first-principles calculations. This EAM potential is applied to Cu, Ag, Cu and Pt metals successfully and the results of basic properties agreed with the experiments. For the same metal, the cohesive energy of fcc structures are the lower than bcc structures.

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CALCULATION FOR A Cu(001) SURFACE WITH AN IMPURITY ATOM

International Journal of Modern Physics B ◽

10.1142/s0217979299000242 ◽

1999 ◽

Vol 13 (04) ◽

pp. 389-396

Author(s):

CHIH-KAI YANG

Keyword(s):

Electronic Structure ◽

Impurity Atom ◽

Magnetic Moments ◽

Tight Binding ◽

Real Space ◽

Structure Calculation ◽

Spin Polarized ◽

Densities Of States ◽

Self Consistent ◽

Local Densities

I use a self-consistent electronic structure calculation to study the system of Cu(001) that has an impurity atom replacing one of the surface Cu atoms. The calculation makes use of the tight-binding linear muffin-tin orbitals (TB-LMTO) and is carried out in real space. I am able to derive the spin-polarized local densities of states for the impurity Cr and Fe respectively, which have peaks below the Fermi level. Charge transfers between the impurities and their neighbors also result in different distributions of magnetic moments for the two impurity systems, with the Cr having approximately 0.5μ B and the Fe atom having a negligible magnetic moment.

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The Real-Space Multiple-Scattering Theory and the Electronic Structure of Grain Boundaries.

MRS Proceedings ◽

10.1557/proc-229-129 ◽

1991 ◽

Vol 229 ◽

Cited By ~ 1

Author(s):

Erik C. Sowa ◽

A. Gonis ◽

X. -G. Zhang

Keyword(s):

Electronic Structure ◽

Grain Boundaries ◽

Multiple Scattering ◽

Scattering Theory ◽

Real Space ◽

Extended Defects ◽

Multiple Scattering Theory ◽

Surfaces And Interfaces ◽

Densities Of States ◽

Electronic Densities

AbstractWe describe the recently developed real-space multiple-scattering theory (RSMST), which is designed for performing first-principles electronic-structure calculations of extended defects, such as surfaces and interfaces including atomic relaxations and with or without impurities, without using artificial periodic boundary conditions. We present the results of non-charge-selfconsistent RSMST calculations of the local electronic densities of states at twist and tilt grain boundaries in fcc Cu and bcc Nb, and report on progress towards the implementation of charge self-consistency and total-energy capabilities.

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