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TiV_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 titanium-vanadium (Ti-V). 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 Ti and V. 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 Ti4V by Materials Project

Ti4V crystallizes in the orthorhombic Fmmm space group. The structure is three-dimensional. there are two inequivalent Ti sites. In the first Ti site, Ti is bonded in a 8-coordinate geometry to two equivalent Ti and two equivalent V atoms. Both Ti–Ti bond lengths are 2.93 Å. Both Ti–V bond lengths are 2.61 Å. In the second Ti site, Ti is bonded in a distorted body-centered cubic geometry to eight Ti atoms. There are four shorter (2.77 Å) and two longer (2.80 Å) Ti–Ti bond lengths. V is bonded in a 12-coordinate geometry to four equivalent Ti atoms.

36 MATERIALS SCIENCE↗

Materials Data on TiV by Materials Project

TiV crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Ti is bonded in a 8-coordinate geometry to four equivalent Ti and four equivalent V atoms. All Ti–Ti bond lengths are 2.70 Å. All Ti–V bond lengths are 2.71 Å. V is bonded in a 8-coordinate geometry to four equivalent Ti and four equivalent V atoms. All V–V bond lengths are 2.70 Å.

36 MATERIALS SCIENCE↗