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Structural formula: Nb3Al

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

Space group : Pm-3n

JARVIS ID: JLMP-1162

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

185.7 107.8 107.8 0.0 0.0 -0.0
107.8 185.7 107.8 0.0 0.0 -0.0
107.8 107.8 185.7 -0.0 0.0 -0.0
0.0 0.0 -0.0 28.4 -0.0 0.0
0.0 0.0 0.0 -0.0 28.4 0.0
-0.0 -0.0 -0.0 0.0 0.0 28.4

Bv: 133.8 GPa

Gv: 32.6 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
Nb 6 7.536 Download cif file
Al 2 6.208 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 0 0) 2.427 Download cif file
(3 1 1) 2.513 Download cif file
(3 2 0) 2.525 Download cif file
(1 1 1) 2.557 Download cif file
(2 1 0) 2.559 Download cif file
(3 1 0) 2.569 Download cif file
(2 2 1) 2.583 Download cif file
(3 2 2) 2.585 Download cif file
(1 1 0) 2.59 Download cif file
(3 2 1) 2.594 Download cif file
(3 3 1) 2.612 Download cif file
(3 3 2) 2.644 Download cif file
(2 1 1) 2.672 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
-0.1100039548 T1u I
83.2307722186 T1u I
106.882040774 T1g
111.497080452 A2g
122.862354314 T2u
124.413666098 T2g R
136.371079284 Eg R
194.088223402 T1u I
211.606720147 T2u
All phonon mode at Gamma point (cm-1)
-0.1100039548
-0.1100039547
83.2307722186
106.882040774
111.497080452
122.862354314
122.862354315
124.413666098
124.413666098
136.371079284
194.088223402
211.606720147
211.606720147

See also

Links to other databases or papers are provided below

JVASP-11981

mp-796

Energy above hull from mp (eV): 0.053361585