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Dr. Duc Nguyen-Manh

Ph.D (CNRS & Univ. Grenoble)
Habilitation Diploma (CNRS & Univ. Grenoble)
CPhys MInstP

Materials Modeling Laboratory

Department of Materials
University of Oxford
Parks Road
Oxford OX1 3PH

Office: Holder Building, Room 30.23
Tel: +44 1865 273 762
Fax: +44 1865 273 789
Email: manh.nguyen@materials.ox.ac.uk

Current Research Projects
Recent Publications
D.Phil. Projects
Electron Microscopy and Microanalysis Group Homepage
Asian Consortium for Computational Materials Science





Summary of Research Interests

My primary research interest addresses the relationship between electronic properties and atomistic structure of materials .

  • Chemical bonding, structural phase stability and phase transformation in materials.

  • Density functional and tight binding theories to electronic and atomistic structure of materials.

  • Theoretical studies of mechanical strength and crystal defects in intermetallic alloys.

  • Electronic structure of strongly electron correlated materials (transition metal oxydes and sulphides).

  • Electronic structure and atomistic simulations of non-crystalline materials (amorphous, quasi-crystals and liquids).



     

    Current Research Projects

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    Study of amorphous covalent materials by atomistic modelling and electron microscopy
    Dr. D. Nguyen-Manh, Prof. D.J.H. Cockayne, Dr. W. McBride, Prof. D.G. Pettifor, Prof. D. McKenzie*,
    Recent experimental observations at nanoscale reveals new and interesting properties of atomic structure for amorphous materials. In particular, the discovery of so-called medium-range order in addition to the conventional short-range order in amorphous covalent systems requires a large-scale and accurate interatomic potentials for describing structural model. This project aimes to combine a new environment-dependent and analytic bond-order potentials recently developed at the MML with the new experimental technique developed at the EM group for studying amorphous structure of covalent bonded matetials. Particular interest will be focused on a-C systems where the existence of both types of bonding (sp2 vs. sp3) is a crucial issue in testing structural models. (*University of Sydney)

    Theoretical-experimental study of alloying behaviour of high temperature metal silicides
    Dr. D. Nguyen-Manh, Dr. D. Pankhurst, Prof. D.G. Pettifor, Dr. G. Shao*, Prof. P. Tsakiropoulos*,
    This collaborative research links experiments and first-principles calculations to understand the mutiscale ralationship between electronic structure, crystal structure bonding, and microstructure properties of transition metals silicides. A particular attention will be focused on incorporating ab-initio data base into the CALPHAD method for studying metalstable phases. (*University of Surrey)(Funded by EPSRC)

    Effects of directional bonding on deformation and fracture of intermetallics
    Dr. D. Nguyen-Manh, Dr. S. Znam*, M. Mrovec*, Prof. V. Vitek*, Prof. D.G. Pettifor,
    The influence of directional bonding on the deformation and fracture of intermetallics is being investigated at the atomistic level in order to understand why some intermetallics are brittle, whereas others are ductile. (*University of Pennsylvania)

    Analytic environment-dependent tight-binding bond integrals
    Dr. D. Nguyen-Manh, M. Mrovec*, Prof. V. Vitek*, Prof. D.G. Pettifor,
    An explicit expression for the environmental dependence of bond integrals have been derived recently within an orthogonal TB representation. This provides the first reliable method for predicting the analytic behaviour of transferable TB integrals and will help extend the accuracy and applicability of the TB model to technologically important multi-component systems. (*University of Pennsylvania) (Funded by the U.S. Department of Energy, BES Grant no. DE-PG02-98ER45702)

    Angularly-dependent potentials for atomistic simulations
    Prof. D.G. Pettifor, Dr. D. Nguyen-Manh, Dr. D. Pankhurst, Dr. I. Oleinik, Prof. M. Aoki*,
    A novel class of angularly-dependent potentials has recently been derived for covalently bonded systems within the Tight Binding approximation. These so called Bond-Order Potentials (BOPs) are currently being developed for hydrocarbons, semiconductors, transition metals, and intermetallics in order to perform realistic atomistic simulations of their properties. (*Gifu University, Japan) (Funded by British Council Collaborative Research Project)

    Transferability of tight-binding model from first-principles calculations
    Dr. D. Nguyen-Manh, T Saha-Dasgupta*, O.K. Andersen**,
    The transferability problem of tight-binding model is being investigated by using the third-generation of LMTO method developed at Max-Plank Institute for Solid State Physics in Stuttgart. (*S.N. Bose National Centre of Basic Science, India; **Max-Plank Institut fur Festkorperforschung, Germany)

    First principle studies of transition metal sulphides
    D. Nguyen-Manh, Prof. D.G. Pettifor, R. Chauke*, P.S. Ntaohae*, Prof. P.E. Ngoepe*
    The electronic structure, equation of state and structural properties of iron and noble metal sulphides are being predicted using first principles density functional theory. (*Materials Modelling Centre, University of the North, South Africa) (Funded by Royal Society - FRD collaborative project)

    Ab-initio study of phase equilibrium in binary and ternary alloys
    Dr. D. Nguyen-Manh, Dr. A. Pasturel*,
    Availability of ab-initio predictions on the relative stability of various metastable phases are being exploited to provide a reliable database for phase diagram calculations. (*LPMMC-CNRS, France)

    Al(Si)-Mn Quasicrystals: New concepts in Hume-Rothery alloys containing transition metals atoms
    Dr. G. Trambly de Laissadiere*, Dr. D. Nguyen-Manh and Dr. D. Mayou**
    It is well-known that phase stability and properties of sp-valent alloys can be described by conventional Hume-Rothery model where the Fermi energy touches a predominant Brillouin zone. With presence of transition metal elements in a host sp alloy such as in Al(Si)-Mn quasicrystal systems, the classical Hume-Rothery picture is not adequate due to the effect of sp-d hybridization. This project aimes to review diffrent models including ourselves in order to generalise the Hume-Rothery concept, to predict and explain new physical properties observed in this type of materials. (*University of Cergy-Pointoise, Paris,**LEPES-CNRS, Grenoble)

    Study of extended defects in bcc-transition metals using environment-dependent bond order potentials
    Dr. S. Dudarev*, Dr. D. Nguyen-Manh, T. Hudson, Prof. A. Sutton and Prof. D.G. Pettifor
    Recent study of defect energies such as interstistials and dislocations in bcc-TM reveals that the central force many-body interatomic potentials such as Finnis-Sinclair potentials are not accurate for simulations of cascade behaviour. This project aimes to use the new environment-depedent bond-order potentials in order to understand the role of angular-forces in different defect calculations. (*UKAEA Fusion, Culham Science Centre)

    Electronic structure of strongly correlated electrons systems
    Dr. D. Nguyen-Manh, Dr. S. Dudarev*
    Physical properties of a large class of materials displaying strong electron correlation is being investigated with a new simulation programme based on full-potential calculations. (*UKAEA Fusion, Culham Science Centre)

    First-principles simulations of semiconductor/metal interface
    Dr. D. Nguyen-Manh, Dr. S. Mukhopadhyay, Dr. Shao*, Prof. K.P. Homewood*,
    Interfacial energy between a complicated phase of transition metal dicilicides and silicon is being investigated to explain experimental observations by high resolution electron microscopy (HREM). (*University of Surrey)

     



    Recent Publications (2002-1998)

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  • S. Mukhopadhyay and Nguyen-Manh D., Phys. Rev. B., vol. 66, 144408, (2002)
    'Origin of induced Sn magnetic moments in thin Fe/Cr/Sn/Cr mulilayers'

  • Pettifor D.G., Oleinik I, Nguyen-Manh D. and Vitek V., Computational Materials Science, vol. 23, 33, (2002)
    'Bond order potentials: bridging the electronic to atomistic modelling hierachies'

  • Mrovec M., Nguyen-Manh D., Pettifor D.G. and Vitek V., MRS Sym. Proc. Vol. 653, p. Z6.3, (2001)
    'Bond-Order Potential with Analytic Environment-Dependent Tight-Binding Integrals: Application to Bcc-Mo'

  • Kim S., Nguyen-Manh D., G.D.W. Smith and Pettifor, D.G., Phil. Mag. A, vol. 80, 2489-2508, (2000)
    'Site preference of Ru and Pd additions to Gamma-based TiAl intermetallics'

  • Nguyen-Manh D. and Pettifor, D.G., and Vitek V., Phys. Rev. Lett., vol. 85, 4136-4139, (2000)
    'Analytic Environment-Dependent Tight-Binding Bond Integrals: Application to MoSi2'

  • Nakamura H., Nguyen-Manh D. and Pettifor D.G., Journal of Alloys and Compounds, vol. 306, 113-121, (2000)
    'Environmental depedence of screened tight-binding parameters in La2Ni10H14'

  • Shao G., Nguyen-Manh D., Pettifor D.G. and Tsakiropolous P., Phil. Mag. Lett, vol. 80, 703-710, (2000)
    'Omega phase formation in a rapidly solidified Cr-40% Al alloys'

  • Znam S., Nguyen-Manh D., Vitek V. and D.G. Pettifor, in ' Properties of Complex Inorganic Materials', Eds: Meike et.al.,p. 479, (2000)
    'Bond order potentials for transition metal based alloys: Ti-Al and Mo-Si'

  • Mrovec. M., Vitek V., Nguyen-Manh D., Pettifor, D.G., Wang, L.G. and Sob, M., MRS vol.578, 199-204 (1999)
    'Study of Mechanical Behaviour of bcc transition metals using bond-order potentials'

  • Nguyen-Manh D. and Pettifor, D.G., Intermetallics 7 1095-1106 (1999)
    'Electronic structure, phase stability and elastic moduli of AB transition metal aluminides'

  • Nguyen-Manh D. and Pettifor, D.G., in 'Gamma Titanium Aluminides 1999', Eds: Y.W. Kim, et.al., TMS, 175-182 (1999)
    'Origin of O phase and pseudo-twinning in Ti-Al-Nb alloys: a first-principles studies'

  • Shao G., Nguyen-Manh D., Tsakiropolous, P. and Pettifor, D.G., in 'Gamma Titanium Aluminides 1999', Eds: Y.W. Kim, et.al., TMS, 155-162 (1999)
    'How Stable are the Omega Phase in TiAl-X Alloys?'

  • Nguyen-Manh D., in 'Trends in Materials Science and Technology', Eds: F.F. Bekker, et.al., 120-127 (1999)
    'Materials Science from first-principles modelling: range of application problems, recent developments and future prospects'

  • Thang C.V., Nguyen-Manh, D., Thuy N.P., and Bruck, E., NAGANO Magel'99 Proceeding, 247-250 (1999)
    'Magnetic properties and electronic structure of RCo4M compounds (R: Y, Gd; M: B, Al, Si)'

  • Nguyen-Manh D., Ntoahae P.S., Pettifor D.G., Ngoepe, P.E., Molecular Simulation vol.22, 23-30, (1999)
    'Electronic structure of platinum-group minerals: prediction of semiconductor band gaps',

  • Sithole H.M., Nguyen-Manh D., Pettifor D.G., Ngoepe, P.E., Molecular Simulation vol.22, 31-37, (1999)
    'Internal relaxation, band gaps and elastic constant calculations of FeS2'

  • Mrovec. M., Vitek V., Nguyen-Manh, D., Pettifor and Sob M., MRS vol. 538, 529-534, (1999)
    'Bond order potentials for bcc transition metals: assessment of their quality and comparison with other methods'

  • Nakamura H., Nguyen-Manh D. and Pettifor D.G., Journal of Alloys and Compounds, vol. 281, 81-91, (1998)
    'Electronic structure and energetics of LaNi5, alpha-La2Ni10H and beta-La2Ni10H14'

  • Kenny S.D., Nguyen-Manh D., Fujitani H. and Sutton, A.P., Phil. Mag. Lett., vol. 78, 469-476, (1998)
    'Ab initio modelling of alumina'

  • Lebacq O., Pasturel A., Nguyen-Manh D., Finel A., Caudon R. and Barrachin, J. Alloys and Compounds, vol. 264, 31-40, (1998)
    'Electronic structure, cohesive properties and phase stability in Ni3V, Pd3V and Pt3V'

  • Nguyen-Manh D., Pettifor D.G., S. Znam and Vitek V., MRS vol. 491, 353-359, (1998)
    'Negative Cauchy Pressure within the Tight-Binding Approximation'

  • Nguyen-Manh D., Pettifor D.G., Sithole H., Ngoepe P.E., Arcangeli, R. Tank and O. Jepsen, MRS vol. 491, 401-406, (1998)
    'Electronic structure, pressure dependence and optical properties of Fes2'

  • Nguyen-Manh D., Tsymbal E.Y., Pettifor D.G., Arcangeli C., Tank R., Andersen O.K. and Paturel A., MRS vol. 492, 319-324 (1998)
    'Spin-polarized density of states and electronic tunnelling from Co/Al2O3 interface'

  • Neumann A., Nguyen-Manh D., Kjekshus A. and Sutton A., Phys. Rev. B, vol. 57, 11149-11156 (1998)
    'Electronic structure and structural stability of ternary AuCo2(1-u)Sn4 and AuNi2Sn4 phases'

  • Shao G., Yang Z., Nguyen-Manh D. and Homewood K.P., J. Mat. Science Letters, vol. 17, 1243-1247, (1998)
    'Fine structure of beta-FeSi2 formed out from alpha-FeSi2 decomposition'

  • Nakamura H., Nguyen-Manh D. and Pettifor D.G., MRS vol. 513, 73-79 (1998)
    'Electronic structure and energetics of LaNi5, alpha-La2Ni10H and beta-La2Ni10H14'.



    D.Phil. Projects

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    ENVIRONMENT-DEPENDENT AND ANALYTIC BOND-ORDER POTENTIALS FOR BCC TRANSITION METALS

    New analytic and environment-dependent bond-order potentials (BOPs) for bcc-TM with analytic forces so that relatively fast Molecular Dynamic simulations can be performed is being constructed. The main idea of this project is to extent the two recent MML developments on analytic BOPs for the sp-valent systems and on analytic screening function for the bond integrals into the d-valent systems of bcc-TM where the angular-forces are crucial. within atomistic simulations (in collaboration with Prof. D.G. Pettifor).

    ATOMISTIC LEVEL STUDIES OF DUCTILITY IN WITH MIXED METALLIC AND COVALENT BONDING .

    The goal of this project is to advance our fundamental understading of deformation and fracture mechanism in materials with mixed metallics and covalent bonding. This type of bonding is common in materials that are important in both structural and functional applications. We propose to concentrate in this research on transition metal silicides, in particular MoSi2, and iridium. (in collaboration with Prof. V. Vitek, University of Pennsylvania).

    Also see a full listing of New projects available within the Department of Materials.