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TaTi_BCC_SolidSolution_128atoms_VASP6

We performed density functional theory (DFT) calculations for body-centered-cubic (BCC) structures with 128 lattices sites of solid solution binary alloys tantalum-titanium (Ta-Ti). The electronic structures of alloys have been calculated using Vienna Ab initio Simulation Package (VASP). Within this package the DFT approach is used to reduce many-body Schrodinger equation to set of single particle Kohn-Sham (KS) equations. The generalized electronic exchange-correlation functional is described by generalized gradient approximation with the Perdew-Burke-Ernzerhof parametrization. The electron-ion interactions is described by pseudopotentials developed within the plane-wave basis projector augmented-wave (PAW) approach. These pseudopotentials are available at the VASP portal (http://cms.mpi.univie.ac.at/vasp/). Our calculations have been run with the pseudopotentials treating s and p semi-core states as valence in case for the elements Hf and Nb. The electronic densities and potentials are expanded over plane-waves with energy cutoff of 350 eV. 2x2x2 k-mesh and normal precision were used. The alloys were modeled by supercell containing 128 randomly distributed atoms. At initial step the atoms occupy perfect bcc lattice cites. This initial structure was optimized until energy changes less than 1e-6 eV, while forces acting on atoms don't exceed 1e-2 eV/angstrom. The electron-ion interaction is described by PAW pseudopotentials. The calculations have been collected by sampling chemical compositions across the entire compositional range. The chemical compositions have been sampled by progressively changing the number of atoms per constituent by 4. For each chemical composition of binaries and ternaries, the first-principle calculations have been run for 100 randomized arrangements of the constituents on the BCC lattice sites. We collected data for a total of 3,100 randomized atomic structures over 31 chemical compositions. The calculations have been collected on Air Force HPC11 cluster using the VASP 6.5.1. Additional methodology and file structure information is available in the dataset README.txt file.

36 MATERIALS SCIENCE↗

Materials Data on TaTi by Materials Project

TiTa is Tungsten-derived structured and crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Ti is bonded in a distorted body-centered cubic geometry to four equivalent Ti and four equivalent Ta atoms. All Ti–Ti bond lengths are 2.83 Å. All Ti–Ta bond lengths are 2.85 Å. Ta is bonded in a distorted body-centered cubic geometry to four equivalent Ti and four equivalent Ta atoms. All Ta–Ta bond lengths are 2.83 Å.

36 MATERIALS SCIENCE↗

Materials Data on TaTi3 by Materials Project

Ti3Ta is Uranium Silicide structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Ti is bonded to eight equivalent Ti and four equivalent Ta atoms to form TiTa4Ti8 cuboctahedra that share corners with twelve equivalent TiTa4Ti8 cuboctahedra, edges with eight equivalent TaTi12 cuboctahedra, edges with sixteen equivalent TiTa4Ti8 cuboctahedra, faces with four equivalent TaTi12 cuboctahedra, and faces with fourteen equivalent TiTa4Ti8 cuboctahedra. All Ti–Ti bond lengths are 2.92 Å. All Ti–Ta bond lengths are 2.92 Å. Ta is bonded to twelve equivalent Ti atoms to form TaTi12 cuboctahedra that share corners with twelve equivalent TaTi12 cuboctahedra, edges with twenty-four equivalent TiTa4Ti8 cuboctahedra, faces with six equivalent TaTi12 cuboctahedra, and faces with twelve equivalent TiTa4Ti8 cuboctahedra.

36 MATERIALS SCIENCE↗

Materials Data on TaTi3 by Materials Project

Ti3Ta crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ti sites. In the first Ti site, Ti is bonded to eight Ti and four equivalent Ta atoms to form TiTa4Ti8 cuboctahedra that share corners with twelve equivalent TiTa4Ti8 cuboctahedra, edges with eight equivalent TaTi12 cuboctahedra, edges with sixteen TiTa4Ti8 cuboctahedra, faces with four equivalent TaTi12 cuboctahedra, and faces with fourteen TiTa4Ti8 cuboctahedra. There are four shorter (2.83 Å) and four longer (2.97 Å) Ti–Ti bond lengths. All Ti–Ta bond lengths are 2.97 Å. In the second Ti site, Ti is bonded to eight equivalent Ti and four equivalent Ta atoms to form TiTa4Ti8 cuboctahedra that share corners with four equivalent TiTa4Ti8 cuboctahedra, corners with eight equivalent TaTi12 cuboctahedra, edges with twenty-four TiTa4Ti8 cuboctahedra, faces with six equivalent TaTi12 cuboctahedra, and faces with twelve TiTa4Ti8 cuboctahedra. All Ti–Ta bond lengths are 2.83 Å. Ta is bonded to twelve Ti atoms to form TaTi12 cuboctahedra that share corners with four equivalent TaTi12 cuboctahedra, corners with eight equivalent TiTa4Ti8 cuboctahedra, edges with eight equivalent TaTi12 cuboctahedra, edges with sixteen equivalent TiTa4Ti8 cuboctahedra, faces with four equivalent TaTi12 cuboctahedra, and faces with fourteen TiTa4Ti8 cuboctahedra.

36 MATERIALS SCIENCE↗