skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Reinterpreting the Cu-Pd Phase Diagram Based on New Ground-State Predictions


No abstract prepared.

; ; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
OSTI Identifier:
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physics. Condensed Matter; Journal Volume: 19; Journal Issue: 2007; Related Information: Article No. 032201
Country of Publication:
United States

Citation Formats

Barthlein, S., Hart, G. L. W., Zunger, A., and Muller, S.. Reinterpreting the Cu-Pd Phase Diagram Based on New Ground-State Predictions. United States: N. p., 2007. Web. doi:10.1088/0953-8984/19/3/032201.
Barthlein, S., Hart, G. L. W., Zunger, A., & Muller, S.. Reinterpreting the Cu-Pd Phase Diagram Based on New Ground-State Predictions. United States. doi:10.1088/0953-8984/19/3/032201.
Barthlein, S., Hart, G. L. W., Zunger, A., and Muller, S.. Mon . "Reinterpreting the Cu-Pd Phase Diagram Based on New Ground-State Predictions". United States. doi:10.1088/0953-8984/19/3/032201.
title = {Reinterpreting the Cu-Pd Phase Diagram Based on New Ground-State Predictions},
author = {Barthlein, S. and Hart, G. L. W. and Zunger, A. and Muller, S.},
abstractNote = {No abstract prepared.},
doi = {10.1088/0953-8984/19/3/032201},
journal = {Journal of Physics. Condensed Matter},
number = 2007,
volume = 19,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
  • The complexity of first-principles total energy calculations limits the pool of structure types considered for a ground-state search for a binary alloy system to a rather small, O(10) , group of ''usual suspects.'' We conducted an unbiased search of fcc-based Ag{sub 1-x}Pd {sub x} structures consisting of up to many thousand atoms by using a mixed-space cluster expansion. We find an unsuspected ground state at 50%-50% composition -- the L1{sub 1} structure, currently known in binary metallurgy only for the Cu{sub 0.5}Pt {sub 0.5} alloy system. We also provide predicted short-range-order profiles and mixing enthalpies for the high temperature, disorderedmore » alloy.« less
  • The f.c.c. superstructure phase diagram for Cu-Pd is calculated by means of isotropic effective interactions derived from an ab initio KKR-CPA electronic-structure calculation. The authors prove the existence of a region in which one-dimensional long-period superstructures are stable. This region is composed of several single-phase fields in which the modulation period is constant and in close agreement with results from high-resolution electron microscopy. The change from wavy antiphase boundaries at low Pd concentration to sharp antiphase boundaries at high Pd concentration is related to a significant change of the interactions with Pd concentration. The role of the Fermi surface andmore » the applicability of the ANNNI model are clarified.« less
  • The ground-state phase diagram of 2D electrons in a high Landau level (index N=2 ) is studied by the density-matrix renormalization group method. Pair correlation functions are systematically calculated for various filling factors from {nu}=1/8 to 1/2 . It is shown that the ground-state phase diagram consists of three different charge density wave states called stripe phase, bubble phase, and Wigner crystal. The boundary between the stripe and the bubble phases is determined to be {nu}{sup s-b}{sub c}{similar_to}0.38 , and that for the bubble phase and Wigner crystal is {nu}{sup b-W}{sub c}{similar_to}0.24 . Each transition is of first order.
  • The periodic Anderson and Kondo lattice model describe the physics of conduction electrons in extended orbitals interacting with strongly correlated electrons in localized orbitals. These models are relevant for the so-called heavy-fermion and related systems such as the Kondo insulators. In this review we summarize recent progress in the understanding of these models, in particular, the one-dimensional Kondo lattice model. The ground-state phase diagram for the one-dimensional Kondo lattice model is determined and shows three distinct phases: a ferromagnetic metallic, an insulating spin liquid, and a paramagnetic metallic state. We present results on these phases obtained from rigorous and approximatemore » analytical calculations supported by various extensive numerical studies on finite-size systems. The ferromagnetic phase appears in the limit of low density of conduction electrons and for strong Kondo coupling away from half filling. On the other hand, the half-filled Kondo lattice has a gap in both spin and charge excitations, i.e., it has a spin-liquid ground state. The paramagnetic phase may be considered as the generic heavy-fermion state and appears in the weak-coupling limit away from half filling. While the former two phases are well understood, the physics of the paramagnetic phase is not worked out in detail yet. In this context various questions will be considered here: Does the Fermi surface include conduction electrons only or also the localized electrons? Does the concept of Luttinger liquid apply in this case? The extension of these results to higher dimensions is also discussed. It is important to notice that the ground states of the Kondo lattice and the periodic Anderson model involve complicated effects, which cannot be understood by simple extension of the single- or two-impurity problem. {copyright} {ital 1997} {ital The American Physical Society}« less