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

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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First Principles Calculations for Metal/Ceramic Interfaces

MRS Proceedings ◽

10.1557/proc-357-427 ◽

1994 ◽

Vol 357 ◽

Cited By ~ 2

Author(s):

M. W. Finnis ◽

C. Kruse ◽

U. SchÖnberger

Keyword(s):

Electronic Structure ◽

High Resolution ◽

Ab Initio ◽

First Principles ◽

Density Functional ◽

Local Density ◽

Work Of Adhesion ◽

First Principles Calculations ◽

Resolution Electron ◽

Metal Ceramic

AbstractWe discuss the recent first principles calculations of the properties of interfaces between metals and oxides. This type of calculation is parameter-free, and exploits the density functional theory in the local density approximation to obtain the electronic structure of the system. At the same time the equilibrium atomic structure is sought, which minimises the excess energy of the interface. Up to now calculations of this type have been made for a few model interfaces which are atomically coherent, that is with commensurate lattices. Examples are Ag/MgO and Nb/Al2O3. In these cases it has been possible to predict the structures observed by high resolution electron microscopy. The calculations are actually made in a supercell geometry, in which there are alternating nanolayers of metal and ceramic. Because of the effectiveness of metallic screening in particular, the interfaces between the nanolayers do not interfere much with each other.Besides the electronic structure of the interface, such calculations have provided values of the ideal work of adhesion. Electrostatic image forces in conjunction with the elementary ionic model provide a simple framework for understanding the results.An important role of such calculations is to develop intuition about the nature of the bonding, including the effects of charge transfer, which has formerly only been described in an empirical way. It may then be possible to build atomistic models of the metal/ceramic interaction which have a sound physical basis and can be calibrated against ab initio results. Simpler models are necessary if larger systems, including misfit dislocations and other defects, are to be simulated, with a view to understanding the atomic processes of growth and failure. Another area in which ab initio calculations can be expected to contribute is in the chemistry of impurity segregation and its effect at interfaces. Such theoretical tools are a natural partner to the experimental technique of high resolution electron energy loss spectroscopy for studying the local chemical environment at an interface.

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Possible Ferroelectricity in SnTiO3 by First-Principles Calculations

MRS Proceedings ◽

10.1557/proc-748-u3.13 ◽

2002 ◽

Vol 748 ◽

Cited By ~ 14

Author(s):

Yoshinori Konishi ◽

Michio Ohsawa ◽

Yoshiyuki Yonezawa ◽

Yoshiya Tanimura ◽

Toyohiro Chikyow ◽

...

Keyword(s):

Electronic Structure ◽

Spontaneous Polarization ◽

First Principles ◽

Local Density Approximation ◽

Lattice Structure ◽

Local Density ◽

Density Approximation ◽

First Principles Calculations ◽

Minimum Total Energy ◽

The Moment

ABSTRACTThe prospect of lattice structure and ferroelectricity of SnTiO3 have been studied by first-principles calculations within local density approximation. The results showed that the SnTiO3 has the minimum total energy within almost tetragonal perovskite structure of a=b=3.80 Å, c=4.09 Å. The calculated electronic structure of SnTiO3 resembles that of PbTiO3 because the Ti 3d states, Sn 5s and 5p states hybridize with the O 2p orbitals. The moment of spontaneous polarization of SnTiO3 was estimated as 73 μ C/cm2, which is as large as that of PbTiO3.

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Effective masses and electronic structure of diamond including electron correlation effects in first principles calculations using the GW-approximation

AIP Advances ◽

10.1063/1.3630932 ◽

2011 ◽

Vol 1 (3) ◽

pp. 032139 ◽

Cited By ~ 21

Author(s):

Henrik Löfås ◽

Anton Grigoriev ◽

Jan Isberg ◽

Rajeev Ahuja

Keyword(s):

Electronic Structure ◽

Electron Correlation ◽

First Principles ◽

First Principles Calculations ◽

Correlation Effects ◽

Gw Approximation ◽

Effective Masses ◽

Electron Correlation Effects

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Correlation effects on the electronic structure of Co2VGa1−xSix (x = 0, 0.25, 0.5, 0.75 and 1) quaternary Heusler alloys: First-principles calculations

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.08.258 ◽

2019 ◽

Vol 771 ◽

pp. 1062-1071 ◽

Cited By ~ 6

Author(s):

Ali Bentouaf ◽

Rezki Mebsout ◽

Brahim Aïssa

Keyword(s):

Electronic Structure ◽

First Principles ◽

Heusler Alloys ◽

First Principles Calculations ◽

Correlation Effects ◽

Quaternary Heusler Alloys

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The Electronic Structure pf Σ5 Grain Boundaries in CU

MRS Proceedings ◽

10.1557/proc-159-395 ◽

1989 ◽

Vol 159 ◽

Cited By ~ 1

Author(s):

Erik C. Sowa ◽

A. Gonis ◽

X.-G. Zhang

Keyword(s):

Electronic Structure ◽

Grain Boundaries ◽

First Principles ◽

Real Space ◽

Embedded Atom Method ◽

First Principles Calculations ◽

Bulk Materials ◽

Embedded Atom ◽

Densities Of States ◽

Self Consistent

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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