Year 2018

• Structural and physical characterization of NpPt2In7

  Publication

  • T. Klimczuk
  • A. Shick
  • S. Khmelevskyi
  • A. Kozub
  • K. Kolincio
  • J. Griveau
  • E. Colineau
  • R. Eloirdi
  • R. Caciuffo

  - JOURNAL OF ALLOYS AND COMPOUNDS - Year 2018

  A new neptunium intermetallic compound, NpPt2In7, has been synthesized in polycrystalline form and characterized by several macroscopic techniques. A Rietveld analysis of its powder x-ray diffraction pattern shows that NpPt2In7 crystallizes in a tetragonal lattice with I4/mmm symmetry and lattice parameters a = 4.58471(3) Å, c = 21.5065(3) Å. Magnetic susceptibility, electrical resistivity, Hall effect, and heat capacity measurements indicate...

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Year 2016

• Electronic structure and magnetism of samarium and neodymium adatoms on free-standing graphene

  Publication

  • A. Kozub
  • A. Shick
  • F. Máca
  • J. Kolorenč
  • A. Lichtenstein

  - PHYSICAL REVIEW B - Year 2016

  The electronic structure of selected rare-earth atoms adsorbed on a free-standing graphene was investigated using methods beyond the conventional density functional theory (DFT+U, DFT +HIA, and DFT+ED). The influence of the electron correlations and the spin-orbit coupling on the magnetic properties has been examined. The DFT+U method predicts both atoms to carry local magnetic moments (spin and orbital) contrary to a nonmagnetic...

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Year 2015

• Ferro- and antiferro-magnetism in (Np, Pu)BC

  Publication

  • T. Klimczuk
  • A. Shick
  • A. Kozub
  • J. Griveau
  • E. Colineau
  • M. Falmbigl
  • F. Wastin
  • P. Rogl

  - APL Materials - Year 2015

  Two new transuranium metal boron carbides, NpBC and PuBC, have been synthesized. Rietveld refinements of powder XRD patterns of {Np,Pu} BC confirmed in both cases isotypism with the structure type of UBC. Temperature dependent magnetic susceptibility data reveal antiferromagnetic ordering for PuBC below T-N = 44 K, whereas ferromagnetic ordering was found for NpBC below T-C = 61 K. Heat capacity measurements prove the bulk character...

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• Site-selective magnetic order of neptunium inNp2Ni17

  Publication

  • A. Hen
  • N. Magnani
  • J. Griveau
  • R. Eloirdi
  • E. Colineau
  • J. Sanchez
  • I. Halevy
  • A. Kozub
  • A. Shick
  • I. Orion
  • R. Caciuffo

  - PHYSICAL REVIEW B - Year 2015

  We present the results obtained by superconducting quantum interference device (SQUID) magnetometry, specific heat, and Mossbauer spectroscopy measurements carried out on Np2Ni17 polycrystalline samples. We show that long-range magnetic order, with a moment mu((2b)) similar to 2.25 mu(B), occurs below T-N = 17.5 K on the Np (2b) sites. A nontrivial situation is observed in that the other Np sites (2d) do not take part to the order...

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• Superconductivity in the niobium-rich compound Nb5Se4

  Publication

  • T. Klimczuk
  • K. Baroudi
  • J. Krizan
  • A. Kozub
  • R. Cava

  - JOURNAL OF ALLOYS AND COMPOUNDS - Year 2015

  The niobium rich selenide compound Nb5Se4 was synthesized at ambient pressure by high-temperature solid–state reaction in a sealed Ta tube. Resistivity and heat capacity measurements reveal that this compound is superconducting, with a Tc = 1.85K. The electronic contribution to the specific heat γ and the Debye temperature are found to be 18.1 mJmol−1K−2 and 298 K respectively. The calculated electron-phonon coupling constant λep...

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• Theory of valence-band and core-level photoemission from plutonium dioxide

  Publication

  • J. Kolorenč
  • A. Kozub
  • A. Shick

  - Journal of Physics : Conference Series - Year 2015

  The correlated-band theory implemented as a combination of the local-density approximation with the dynamical mean-field theory is applied to PuO2. An insulating electronic structure, consistent with the experimental valence-band photoemission spectra, is obtained. The calculations yield a nonmagnetic ground state that is characterized by a noninteger filling of the plutonium 5f shell. The noninteger filling as well as the satellites...

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Year 2013

• Structure and paramagnetism in weakly correlated Y8Co5

  Publication

  • T. Klimczuk
  • V. A. .. Sidorov
  • A. Szajek
  • M. Werwiński
  • S. A. J. Kimber
  • A. Kozub
  • D. Safarik
  • J. D. Thompson
  • R. J. Cava

  - JOURNAL OF PHYSICS-CONDENSED MATTER - Year 2013

  We report the basic physical properties of monoclinic Y8Co5 determined by means of magnetic susceptibility, electrical resistivity, and specific heat measurements. The crystal structure of Y8Co5 is monoclinic (P21/c) with lattice parameters a = 7.0582(6) Å, b = 7.2894(6) Å, c = 24.2234(19) Å, and β = 102.112(6)° as refined by using synchrotron powder x-ray diffraction data. The compound shows temperature independent paramagnetism...

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Year 2012

• Study of Icosahedral Clusters in Close-packed Simple Liquids

  Publication

  • A. Kozub

  - TASK Quarterly - Year 2012

  The local structure of liquid copper was determined using Steinhardt order parameters, with particular attention paid to icosahedral clusters. The positions of atoms were obtained from three sets of molecular dynamics simulations, with the forces obtained from: the Sutton-Chen (SC) potential, the Naval Research Laboratory total energy tight-binding (NRL-TB) method and the divide-and-conquer learn-on-the-fly (DCLOTF) method, respectively....

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