Prototype fcc-based binary-alloy phase diagrams from tight-binding electronic-structure calculations

Third neighbor analytic tight-binding formulae were obtained for graphene sheets and nanotubes. After fitting the corresponding of-diagonal matrix elements can be used in numerical electronic structure calculations of nanotubes and corrugated graphene.

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Site Occupancies in Ternary C15 Ordered Laves Phases

MRS Proceedings ◽

10.1557/proc-460-617 ◽

1996 ◽

Vol 460 ◽

Cited By ~ 6

Author(s):

P. G. Kotula ◽

I. M. Anderson ◽

F. Chu ◽

D. J. Thoma ◽

J. Bentley ◽

...

Keyword(s):

Electronic Structure ◽

Total Energy ◽

Phase Diagrams ◽

First Principles ◽

Site Occupancy ◽

Electronic Structure Calculations ◽

Laves Phase ◽

Laves Phases ◽

Structure Calculations

ABSTRACTSite occupancies in three C15-structured AB2(X) Laves phases have been determined with Atom Location by CHanneling Enhanced MIcroanalysis (ALCHEMI). In NbCr2(V), the results are consistent with exclusive site occupancies of Nb for the A sublattice and Cr and V for the A sublattice. The B-site occupancy of V can be interpreted in terms of electronic structure. In NbCr2(Ti), the results are consistent with Ti partitioning mostly to the A sites with some anti-site defects likely. In HfV2(Nb), the results are consistent with Nb partitioning between the A and A sites. The results of the ALCHEMI analyses of these ternary C15 Laves phase materials are discussed with respect to previously determined phase diagrams and first-principles total energy and electronic structure calculations.

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Comparative study of tight-binding and ab initio electronic structure calculations focused on magnetic anisotropy in ordered CoPt alloy

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2013.12.040 ◽

2014 ◽

Vol 356 ◽

pp. 87-94 ◽

Cited By ~ 6

Author(s):

J. Zemen ◽

J. Mašek ◽

J. Kučera ◽

J.A. Mol ◽

P. Motloch ◽

...

Keyword(s):

Electronic Structure ◽

Comparative Study ◽

Magnetic Anisotropy ◽

Ab Initio ◽

Tight Binding ◽

Electronic Structure Calculations ◽

Structure Calculations ◽

Ab Initio Electronic Structure

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Surface Segregation Maps Derived from Tight-Binding Ising Model

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.172-174.1008 ◽

2011 ◽

Vol 172-174 ◽

pp. 1008-1015 ◽

Cited By ~ 6

Author(s):

Jean Marc Roussel ◽

Guy Tréglia ◽

Bernard Legrand

Keyword(s):

Experimental Data ◽

Electronic Structure ◽

Ising Model ◽

Surface Energy ◽

Surface Segregation ◽

Tight Binding ◽

Electronic Structure Calculations ◽

Matrix Elements ◽

Metal Element ◽

Structure Calculations

Surface segregation in transition metals can be analysed within a generalised Ising model,derived from Tight-Binding electronic structure calculations, which identiﬁes three driving forces:the difference in surface energy and atomic volume between the two components and their tendencyto order or phase separate in the bulk. Using this ”three effects” rule, we present here general mapswhich predict the tendency of the solute metal element to segregate (or not) at the surface of a metalmatrix, for the 702 solute/matrix systems that can be formed with transition metal elements. Ourpredictions compare fairly well to the existing ab initio calculations and experimental data availableon these systems. The few exceptions, which mainly concern given matrix elements are discussed indetails.

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