Now showing items 1-20 of 29

    • Antiphase boundary energy of Ni3Al with Ti impurities from Monte Carlo simulations 

      Sun, Ruoshi; van de Walle, Axel (2016-04-07)
      {111}<110> antiphase boundary (APB) energy of Ni3Al with varying Ti impurity concentration (x=0.1, 1, 10%) and temperature (T=400, 600, 800, 1000, 1200, 1400, 1600 K) are obtained from cluster expansion and Monte Carlo ...
    • Ti-X (X=Al, V, Nb, Ta, Mo, Zr, and Sn) impurity diffusion coefficients from first-principles calculations 

      Xu, Weiwei; Shang, ShunLi; Zhou, Bi-Cheng; Wang, Yi; Liu, Xingjun; Wang, Cuiping; Liu, Zi-Kui
      Knowledge of diffusivity is fundamental to our understanding of diffusion mechanism and design of materials. Despite various elements dissolved in industrial Ti alloys to improve their performance, diffusion coefficients ...
    • MoS2-MoTe2 

      Burton, Benjamin P; Singh, Arunima
      A first principles phase diagram calculation, that included van der Waals interactions, was performed for the system (1-X)$\cdot$MoS$_{2}$-(X)$\cdot$MoTe$_{2}$. Surprisingly, the predicted phase diagram has at least ...
    • NaCl-KCl 

      Burton, Bejnamin P.; van de Walle, Axel
      First principles phase diagram calculations were performed for the system NaCl-KCl. Planewave pseudopotential calculations of formation energies were used as a basis for fitting cluster expansion Hamiltonians, both with- ...
    • CaCO3-MgCO3 and CdCO3-MgCO3 

      Burton, Bejnamin P. (2014-11-20)
      Planewave pseudopotential calculations of supercell total energies were used as bases for firstprinciples calculations of the CaCO3–MgCO3 and CdCO3–MgCO3 phase diagrams. Calculated phase diagrams are in qualitative to ...
    • First principles phase diagram calculations for the wurtzite-structure systems AlN-GaN, GaN-InN, and AlN-InN 

      Burton, Bejnamin P.; van de Walle, Axel; kattner, Ursula (2014-11-20)
      First principles phase diagram calculations were performed for the wurtzite-structure quasibinary systems AlN–GaN, GaN–InN, and AlN–InN. Cluster expansion Hamiltonians that excluded, and included, excess vibrational ...
    • TiO_X 

      Burton, Bejnamin P.; van de Walle, Axel (2014-09-29)
      First principles based phase diagram calculations were performed for the hexagonal closest packed octahedral-interstitial solid solution system aTiOX, or aTi½ 1 XOX ([ ]¼Vacancy; 0rXr1=2), by the cluster expansion (CE) ...
    • Elemental vacancy diffusion for fcc and hcp structures - spreadsheets for plots 

      Angsten, Thomas; Mayeshiba, Tam; Wu, Henry; Morgan, Dane (2014-09-18)
      See entry at http://hdl.handle.net/11256/76 for Angsten T et al (2014) Elemental vacancy diffusion database from high-throughput first-principles calculations for fcc and hcp structures. New J. Phys. 16 015018 http: ...
    • Ta Melting Point Calculation by Small-cell Coexistence Method 

      Hong, Qijun; van de Walle, Axel (2014-08-16)
      We calculate the melting temperature of Tantalum, by employing the small-size coexistence solid-liquid coexistence method. Two pseudo-potentials are employed, namely Ta_v (5d^3 6s^2) and Ta_pv (5p^6 5d^3 6s^2). Results ...
    • Np incorporation into metal organic frameworks 

      Saha, Saumitra; Becker, Udo (2014-08-11)
    • Li-Ni-Mn-Co-Ti-O Voltage Profile 

      Markus, Isaac M; Asta, Mark (2014-08-11)
      The performance enhancements associated with Ti substitution of Co in the layered cathode material Li1(NixMnxCo1-2x)O2 were investigated using density functional theory calculations. Examining the structural and electronic ...
    • GeTe-PbTe PbS-PbTe PbSe-PbS PbTe-PbSe PbTe-SnTe SnTe-GeTe mixing and coherency strain energies 

      Doak, Jeff W.; Wolverton, C. (2012-10-15)
      Nanostructures formed by phase separation improve the thermoelectric figure of merit in lead chalcogenide semiconductor alloys, with coherent nanostructures giving larger improvements than incoherent nanostructures. However, ...
    • Electronic structures of long periodic stacking order structures in Mg: A first-principles study 

      Wang, William Yi; Shang, Shun Li; Wang, Yi; Darling, Kristopher A.; Kecskes, Laszlo J; Mathaudhu, Suveen N.; Hui, Xi Dong; Liu, Zi-Kui (2014-08-08)
      Long period stacking order (LPSO) structures, such as 6H, 10H, 14H, 18R and 24R, play significant roles in enhancing the mechanical properties of Mg alloys and have been largely investigated separately. In the present ...
    • Elemental vacancy diffusion for fcc and hcp structures 

      Angsten, Thomas; Mayeshiba, Tam; Wu, Henry; Morgan, Dane (2014-08-08)
      This work demonstrates how databases of diffusion-related properties can be developed from high-throughput ab initio calculations. The formation and migration energies for vacancies of all adequately stable pure elements ...
    • Diffusion under stress of Si impurities in Ni: a first principles study 

      Manga, Venkateswara R; Trinkle, Dallas R.; Bellon, Pascal (2014-08-01)
    • ZrSiO4-HfSiO4 

      Burton, Benjamin (2013-05-09)
      ZrSiO4 and HfSiO4 are of considerable interest because of their low thermal expansions, thermal conductivities, and the optical properties of HfSiO4. In addition, silicate phases of both are studied as model radioactive ...
    • Ti-O-M interaction between oxygen and metal (M) substitution in titanium for oxygen diffusion change 

      Wu, Henry H. (2013-05-28)
      We calculate first-principles interaction energies between substitutional solutes and oxygen interstitials in α-titanium and predict the effect of solutes on oxygen diffusion from those interactions. Interaction between ...
    • Au - HCP - Migration energy 

      Morgan, Dane (2013-05-06)
      Migration energy for HCP gold, self-diffusion.
    • TiO2: On the possibility of ferromagnetism 

      Yang, Kesong (2013-04-08)
      To see if ferromagnetism can occur in C-doped anatase TiO2, we performed first-principles calculations for a number of C-doped structures in which C atoms substitute O atoms. Our study shows that each C has spin-polarized ...