The Experts below are selected from a list of 138 Experts worldwide ranked by ideXlab platform
J Hafner - One of the best experts on this subject based on the ideXlab platform.
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effective Interatomic Forces and atomic and electronic structure of liquid and amorphous metals
Journal of Physics: Condensed Matter, 1991Co-Authors: J HafnerAbstract:The state of the art in the calculation of Interatomic Forces in s, p and d-bonded metals and alloys, and their application in the atomistic simulation of the structural and electronic properties of liquid and amorphous phases are reviewed.
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a novel hybridised nearly free electron tight binding bond approach to Interatomic Forces in disordered transition metal alloys application to the modelling of metallic glasses
Journal of Physics: Condensed Matter, 1990Co-Authors: C Hausleitner, J HafnerAbstract:The authors present a novel hybridised nearly-free-electron tight-binding-bond approach to Interatomic Forces in topologically disordered transition-metal alloys and a first application to the atomistic simulation of transition-metal glasses.
C Hausleitner - One of the best experts on this subject based on the ideXlab platform.
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Microscopic approach to the structure of transition-metal glasses.
Physical Review B, 1990Co-Authors: C Hausleitner, Jürgen HafnerAbstract:A novel hybridized nearly-free-electron\char21{}tight-binding-bond approach to the Interatomic Forces in disordered transition-metal alloys is used to construct realistic models for the atomic structure of amorphous alloys.
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a novel hybridised nearly free electron tight binding bond approach to Interatomic Forces in disordered transition metal alloys application to the modelling of metallic glasses
Journal of Physics: Condensed Matter, 1990Co-Authors: C Hausleitner, J HafnerAbstract:The authors present a novel hybridised nearly-free-electron tight-binding-bond approach to Interatomic Forces in topologically disordered transition-metal alloys and a first application to the atomistic simulation of transition-metal glasses.
A Pasturel - One of the best experts on this subject based on the ideXlab platform.
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Bonding Mechanisms and Interatomic Forces in Ni-Al Liquid Alloys
NATO ASI Series, 1994Co-Authors: A PasturelAbstract:In the past decade, it has been a goal to combine at a high level of accuracy both quantum-mechanical and statistical-thermodynamical contributions to obtain a theoretical knowledge of the phase diagrams. One of the most efficient statistical-mechanics techniques in the Cluster-Variational method (CVM), which provides a good description of the free energy as a function of the short-range order 1. Based on a cluster expansion of the configurational free energy, it has been essentially used to deal with solid solutions or ordered phases presenting an extended concentration range. However liquid alloys may also display chemical short range order (CSRO) as has been shown recently for a series of metallic alloys 2 and it appears as essential to consider this when determining their thermodynamic quantities.
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Interatomic Forces and atomic structure of liquid al80mn20 bin alloys
Journal of Physics: Condensed Matter, 1993Co-Authors: Do L Phuong, Nguyen D Manh, A PasturelAbstract:A tight-binding-bond approach to Interatomic Forces in disordered aluminium-transition-metal (Al-M) alloys is presented. The bond order is calculated on a Bethe lattice reference system, well adapted to topologically disordered alloys. It is shown that the bond order depends strongly on the strength of the pd hybridization in the Al-M alloy, leading to non-additive potentials with a strong preference for the formation of pairs of unlike atoms and short bond distances in the Al-M pairs. This is illustrated by studying the structural properties of liquid Al80Mn20 alloy using molecular-dynamics simulations and by comparing the results with the available experimental ones.
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Interatomic Forces and atomic structure of liquid Al80Mn20/bin alloys
Journal of Physics: Condensed Matter, 1993Co-Authors: L. Do Phuong, D. Nguyen Manh, A PasturelAbstract:A tight-binding-bond approach to Interatomic Forces in disordered aluminium-transition-metal (Al-M) alloys is presented. The bond order is calculated on a Bethe lattice reference system, well adapted to topologically disordered alloys. It is shown that the bond order depends strongly on the strength of the pd hybridization in the Al-M alloy, leading to non-additive potentials with a strong preference for the formation of pairs of unlike atoms and short bond distances in the Al-M pairs. This is illustrated by studying the structural properties of liquid Al80Mn20 alloy using molecular-dynamics simulations and by comparing the results with the available experimental ones.
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a tight binding bond approach to Interatomic Forces in disordered transition metal alloys
MRS Proceedings, 1992Co-Authors: A PasturelAbstract:A tight-binding-bond approach to Interatomic Forces in disordered transition metal-Aluminium alloys is presented. The bond-order is calculated on a Bethe lattice reference system, well adapted to topologically disordered alloy. It is shown that the bond-order depends strongly on the strength of the pd hybridization in the AB alloy, leading to non additive potentials with a strong preference for the formation of pair of unlike atoms and short bond-distances in the A-B pairs. This is illustrated by studying the structural properties of liquid Al 80 Ni 20 and Al 80 Mn 20 alloys using molecular dynamics simulations and by comparing our results with the available experimental ones.
Huajie Chen - One of the best experts on this subject based on the ideXlab platform.
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locality of Interatomic Forces in tight binding models for insulators
Mathematical Modelling and Numerical Analysis, 2020Co-Authors: Christoph Ortner, Jack Thomas, Huajie ChenAbstract:The tight binding model is a minimalistic electronic structure model for predicting properties of materials and molecules. For insulators at zero Fermi-temperature we show that the potential energy surface of this model can be decomposed into exponentially localised site energy contributions, thus providing qualitatively sharp estimates on the Interatomic interaction range which justifies a range of multi-scale models. For insulators at finite Fermi-temperature we obtain locality estimates that are uniform in the zero-temperature limit. A particular feature of all our results is that they depend only weakly on the point spectrum. This work extends and strengthens (Chen, Ortner 2016) and (Chen, Lu, Ortner 2018) for finite temperature models.
Shiwei Zhang - One of the best experts on this subject based on the ideXlab platform.
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communication calculation of Interatomic Forces and optimization of molecular geometry with auxiliary field quantum monte carlo
Journal of Chemical Physics, 2018Co-Authors: Mario Motta, Shiwei ZhangAbstract:We propose an algorithm for accurate, systematic, and scalable computation of Interatomic Forces within the auxiliary-field quantum Monte Carlo (AFQMC) method. The algorithm relies on the Hellmann-Feynman theorem and incorporates Pulay corrections in the presence of atomic orbital basis sets. We benchmark the method for small molecules by comparing the computed Forces with the derivatives of the AFQMC potential energy surface and by direct comparison with other quantum chemistry methods. We then perform geometry optimizations using the steepest descent algorithm in larger molecules. With realistic basis sets, we obtain equilibrium geometries in agreement, within statistical error bars, with experimental values. The increase in computational cost for computing Forces in this approach is only a small prefactor over that of calculating the total energy. This paves the way for a general and efficient approach for geometry optimization and molecular dynamics within AFQMC.