Simple rules for the understanding of Heusler compounds
IBM1
TL;DR: Heusler compounds as discussed by the authors are a remarkable class of intermetallic materials with 1:1:1 or 2:1-1 composition comprising more than 1500 members, and their properties can easily be predicted by the valence electron count.
About: This article is published in Progress in Solid State Chemistry.The article was published on 2011-05-01. It has received 1675 citations till now. The article focuses on the topics: Heusler compound.
Citations
More filters
TL;DR: A current snapshot of high-throughput computational materials design is provided, and the challenges and opportunities that lie ahead are highlighted.
Abstract: High-throughput computational materials design is an emerging area of materials science. By combining advanced thermodynamic and electronic-structure methods with intelligent data mining and database construction, and exploiting the power of current supercomputer architectures, scientists generate, manage and analyse enormous data repositories for the discovery of novel materials. In this Review we provide a current snapshot of this rapidly evolving field, and highlight the challenges and opportunities that lie ahead.
1,568 citations
TL;DR: In this paper, the authors review the basic concepts and compare these topological states of matter from the materials perspective with a special focus on Weyl semimetals, and introduce the signatures of Weyl points in a pedagogical way, from Fermi arcs to the chiral magnetotransport properties.
Abstract: Topological insulators and topological semimetals are both new classes of quantum materials, which are characterized by surface states induced by the topology of the bulk band structure. Topological Dirac or Weyl semimetals show linear dispersion around nodes, termed the Dirac or Weyl points, as the three-dimensional analog of graphene. We review the basic concepts and compare these topological states of matter from the materials perspective with a special focus on Weyl semimetals. The TaAs family is the ideal materials class to introduce the signatures of Weyl points in a pedagogical way, from Fermi arcs to the chiral magnetotransport properties, followed by hunting for the type-II Weyl semimetals in WTe2, MoTe2, and related compounds. Many materials are members of big families, and topological properties can be tuned. As one example, we introduce the multifunctional topological materials, Heusler compounds, in which both topological insulators and magnetic Weyl semimetals can be found. Instead of a comp...
1,194 citations
TL;DR: In this article, the authors present design criteria and testing results for a new open-source "GBRV" ultrasoft pseudopotential library that has been optimized for use in high-throughput DFT calculations.
1,077 citations
TL;DR: The magnetocaloric effect and its most straightforward application, magnetic refrigeration, are topics of current interest due to the potential improvement of energy efficiency of cooling and temperature control systems, in combination with other environmental benefits associated to a technology that does not rely on the compression/expansion of harmful gases.
941 citations
TL;DR: A high zT of ∼1.5 at 1,200 K is reported for the p-type FeNbSb heavy-band half-Heusler alloys with enhanced point-defect and electron–phonon scatterings and a significant reduction in the lattice thermal conductivity, highlighting the optimization strategy forheavy-band thermoelectric materials.
Abstract: Thermoelectric materials could be used to convert waste heat into useful electricity, but the ideal substance needs to both optimize the electrical power factor and suppress thermal conductivity. Here, the authors report a high figure of merit of 1.5 at 1,200 K in the p-type half-Heusler alloy FeNbSb.
862 citations
References
More filters
TL;DR: A simple derivation of a simple GGA is presented, in which all parameters (other than those in LSD) are fundamental constants, and only general features of the detailed construction underlying the Perdew-Wang 1991 (PW91) GGA are invoked.
Abstract: Generalized gradient approximations (GGA’s) for the exchange-correlation energy improve upon the local spin density (LSD) description of atoms, molecules, and solids. We present a simple derivation of a simple GGA, in which all parameters (other than those in LSD) are fundamental constants. Only general features of the detailed construction underlying the Perdew-Wang 1991 (PW91) GGA are invoked. Improvements over PW91 include an accurate description of the linear response of the uniform electron gas, correct behavior under uniform scaling, and a smoother potential. [S0031-9007(96)01479-2] PACS numbers: 71.15.Mb, 71.45.Gm Kohn-Sham density functional theory [1,2] is widely used for self-consistent-field electronic structure calculations of the ground-state properties of atoms, molecules, and solids. In this theory, only the exchange-correlation energy EXC › EX 1 EC as a functional of the electron spin densities n"srd and n#srd must be approximated. The most popular functionals have a form appropriate for slowly varying densities: the local spin density (LSD) approximation Z d 3 rn e unif
146,533 citations
TL;DR: In this paper, the Hartree and Hartree-Fock equations are applied to a uniform electron gas, where the exchange and correlation portions of the chemical potential of the gas are used as additional effective potentials.
Abstract: From a theory of Hohenberg and Kohn, approximation methods for treating an inhomogeneous system of interacting electrons are developed. These methods are exact for systems of slowly varying or high density. For the ground state, they lead to self-consistent equations analogous to the Hartree and Hartree-Fock equations, respectively. In these equations the exchange and correlation portions of the chemical potential of a uniform electron gas appear as additional effective potentials. (The exchange portion of our effective potential differs from that due to Slater by a factor of $\frac{2}{3}$.) Electronic systems at finite temperatures and in magnetic fields are also treated by similar methods. An appendix deals with a further correction for systems with short-wavelength density oscillations.
47,477 citations
TL;DR: A way is found to visualize and understand the nonlocality of exchange and correlation, its origins, and its physical effects as well as significant interconfigurational and interterm errors remain.
Abstract: Generalized gradient approximations (GGA's) seek to improve upon the accuracy of the local-spin-density (LSD) approximation in electronic-structure calculations. Perdew and Wang have developed a GGA based on real-space cutoff of the spurious long-range components of the second-order gradient expansion for the exchange-correlation hole. We have found that this density functional performs well in numerical tests for a variety of systems: (1) Total energies of 30 atoms are highly accurate. (2) Ionization energies and electron affinities are improved in a statistical sense, although significant interconfigurational and interterm errors remain. (3) Accurate atomization energies are found for seven hydrocarbon molecules, with a rms error per bond of 0.1 eV, compared with 0.7 eV for the LSD approximation and 2.4 eV for the Hartree-Fock approximation. (4) For atoms and molecules, there is a cancellation of error between density functionals for exchange and correlation, which is most striking whenever the Hartree-Fock result is furthest from experiment. (5) The surprising LSD underestimation of the lattice constants of Li and Na by 3--4 % is corrected, and the magnetic ground state of solid Fe is restored. (6) The work function, surface energy (neglecting the long-range contribution), and curvature energy of a metallic surface are all slightly reduced in comparison with LSD. Taking account of the positive long-range contribution, we find surface and curvature energies in good agreement with experimental or exact values. Finally, a way is found to visualize and understand the nonlocality of exchange and correlation, its origins, and its physical effects.
17,848 citations
TL;DR: For the molecules Be2, F2, and P2 of Table I, the unrestricted Hartree-Fock solution breaks the singlet spin symmetry, even though the density functional solutions do not.
Abstract: For the molecules Be2, F2, and P2 of Table I, the unrestricted Hartree-Fock solution breaks the singlet spin symmetry, even though the density-functional solutions do not. For these broken-symmetry solutions, the UHF atomization energies become 17, 220, and 141 kcalymol, respectively, and the mean absolute error of all the UHF atomization energies becomes 69.8 kcalymol. The PBE correlation energy of the two-electron ions of nuclear charge Z ! ` should be corrected to 20.0479 hartree, consistent with the PBE value v 0.046644 stated in the Letter. The quoted value 20.0482 hartree was obtained from the more refined v 0.046920 of G. G. Hoffman, Phys. Rev. B 45, 8730 (1992). Reference [6] should have been “A. C. Scheiner, J. Baker, and J. W. Andzelm, J. Comput. Chem. (to be published)”.
11,883 citations
TL;DR: This work ascribes this giant magnetoresistance of (001)Fe/(001)Cr superlattices prepared by molecularbeam epitaxy to spin-dependent transmission of the conduction electrons between Fe layers through Cr layers.
Abstract: We have studied the magnetoresistance of (001)Fe/(001)Cr superlattices prepared by molecularbeam epitaxy. A huge magnetoresistance is found in superlattices with thin Cr layers: For example, with ${t}_{\mathrm{Cr}}=9$ \AA{}, at $T=4.2$ K, the resistivity is lowered by almost a factor of 2 in a magnetic field of 2 T. We ascribe this giant magnetoresistance to spin-dependent transmission of the conduction electrons between Fe layers through Cr layers.
7,993 citations