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Structural formula: TiAl2

Force-field: Farkas_Nb-Ti-Al_1996.eam.alloy

Space group : Cmmm

JARVIS ID: JLMP-1169

Download input files

Elastic tensor (GPa)

Elastic tensor for the conventional cell of the system were calculated with LAMMPS in.elastic script at 0 K [Source] . Similar script can be used for temperature dependent elastic constants and will be available here soon. WARNING! Please note that the starting lattice parameters of crystal structures were taken from density functional theory (DFT) and not from experiments. Generic minimization parameters were chosen for LAMMPS run rather than testing them for each individual case such as energy convergence criterion and so on. Hence, there are chances that the calculation gets trapped in a local energy minima. Please read carefully the assumptions taken during calculations in the in.elastic script and use the data at your own risk

273.7 148.2 175.0 0.0 -0.0 -0.0
148.2 243.2 158.7 0.0 -0.0 -0.0
175.0 158.7 277.2 0.0 -0.0 -0.0
0.0 0.0 0.0 109.8 0.0 -0.0
-0.0 -0.0 -0.0 0.0 121.8 -0.0
-0.0 -0.0 -0.0 -0.0 -0.0 88.9

Bv: 195.3 GPa

Gv: 84.9 GPa

Vacancy-formation energy (eV)

Vacancy formation energies were calculated by deleting the symmterically distinct atoms in the system [Source]. In the table, vacancy forming element, its multiplicity, and defect-formation energy are given. The reference element cohesive energies were calculated with the most stable structure for the element found on materials project database. Defect structures were constructed with the fully-relaxed bulk system as input. For defect-structures energetics calculations, constant volume ensemble was used. We impose the defect structures to be at least 1.5 nm large in all directions.

Element Mult. Value
Ti 4 1.895 Download cif file
Al 2 -0.109 Download cif file
Al 2 -0.167 Download cif file
Al 4 0.297 Download cif file

Surface energy (J/m2)

Surface energies were calculated for symmterically distinct crystal surfaces . In the table, (hkl) indices and surface enegies are given. For surface-structure energetics, constant volume ensemble was used. We impose the slab thickness to be at least 2 nm and vaccum size of 2.5 nm. The maximum miller index is taken as 3.

Surface Value
(1 3 1) 1.254 Download cif file
(0 1 0) 1.307 Download cif file
(1 0 0) 1.36 Download cif file
(0 0 1) 1.379 Download cif file
(2 3 2) 1.431 Download cif file
(1 2 1) 1.437 Download cif file
(1 1 1) 1.447 Download cif file
(0 1 3) 1.451 Download cif file
(3 1 0) 1.451 Download cif file
(2 1 0) 1.459 Download cif file
(0 1 2) 1.48 Download cif file
(3 1 3) 1.491 Download cif file
(2 1 2) 1.494 Download cif file
(3 2 3) 1.494 Download cif file
(3 3 1) 1.499 Download cif file
(1 0 1) 1.501 Download cif file
(0 2 3) 1.503 Download cif file
(1 3 0) 1.505 Download cif file
(1 3 3) 1.506 Download cif file
(3 2 0) 1.512 Download cif file
(3 3 2) 1.521 Download cif file
(2 3 3) 1.521 Download cif file
(1 3 2) 1.526 Download cif file
(2 3 0) 1.528 Download cif file
(1 2 2) 1.532 Download cif file
(3 2 1) 1.532 Download cif file
(2 2 1) 1.538 Download cif file
(3 1 1) 1.539 Download cif file
(1 2 3) 1.539 Download cif file
(0 1 1) 1.541 Download cif file
(3 0 1) 1.544 Download cif file
(2 3 1) 1.548 Download cif file
(1 1 3) 1.548 Download cif file
(1 0 3) 1.55 Download cif file
(2 2 3) 1.553 Download cif file
(0 3 2) 1.554 Download cif file
(3 2 2) 1.557 Download cif file
(0 2 1) 1.562 Download cif file
(3 1 2) 1.563 Download cif file
(2 1 3) 1.564 Download cif file
(1 1 2) 1.565 Download cif file
(2 0 3) 1.565 Download cif file
(3 0 2) 1.566 Download cif file
(2 1 1) 1.572 Download cif file
(1 0 2) 1.576 Download cif file
(1 1 0) 1.577 Download cif file
(2 0 1) 1.581 Download cif file
(1 2 0) 1.606 Download cif file
(0 3 1) 1.613 Download cif file

Phonon

Phonons were obtained by making an interface of JARVIS-FF with Phonopy package at 0 K [Source] . For deformed-structures, constant volume ensemble was used. The deofrmed structures were taken of at least 1.5 nm size in all directions. The band-indices for phonon bandstructure was obtained with Pymatgen. The phonon representation were obtained with phonopy. "I" and "R" denotes infrared and Raman active modes respectively

Visualize Phonons here
Phonon mode (cm-1) Representation
-0.0001719833 None
204.198767959 B2 I+R
214.215264302 B1 I+R
228.904243659 B2 I+R
244.254713396 A1 I+R
259.848673287 B1 I+R
292.770941419 A1 I+R
314.239762432 B2 I+R
321.803895398 A1 I+R
330.785078124 B1 I+R
366.514611475 A1 I+R
381.957305244 B1 I+R
395.060751839 A1 I+R
411.205302986 B2 I+R
411.642984576 B2 I+R
471.777674672 B1 I+R
All phonon mode at Gamma point (cm-1)
-0.0001717895
-0.0001712916
-0.0001053058
120.054301068
135.852529023
144.460656525
158.744164955
190.500427847
204.198767959
214.215264302
214.670646459
228.904243659
237.415954846
237.420903679
244.254713396
259.848673287
280.469551559
292.770941419
309.14887615
314.239762432
320.133917516
321.803895398
330.785078124
332.889820099
338.641864247
366.514611475
374.475711436
381.957305244
395.060751839
405.956151755
411.205302986
411.642984576
428.870504541
434.37843644
460.207369897
471.777674672

See also

Links to other databases or papers are provided below

JVASP-16660

mp-11809

Energy above hull from mp (eV): 0.00467513