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Electronic structure [Reference]

The following shows the electronic density of states and bandstructure [Source-code]. DFT is generally predicted to underestimate bandgap of materials. Accurate band-gaps are obtained with higher level methods (with high computational requirement) such as HSE, GW , which are under progress. If available, MBJ data should be comparable to experiments also. Total DOS, Orbital DOS and Element dos [Source-code] buttons are provided for density of states options. Energy is rescaled to make Fermi-energy zero. In the bandstructure plot [Source-code], spin up is shown with blue lines while spin down are shown with red lines. Non-degenerate spin-up and spin-down states (if applicable) would imply a net orbital magnetic moment in the system. Fermi-occupation tolerance for bandgap calculation is chosen as 0.001.

High-symmetry kpoints based bandgap (eV): 1.856I

Total DOS Orbital DOS Element DOS

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Electrostatic potential [Reference]

The following plot shows the plane averaged electrostatic potential (ionic+Hartree) along x, y and z-directions. The red line shows the Fermi-energy while the green line shows the maximum value of the electrostatic potential. For slab structures (with vacuum along z-direction), the difference in these two values can be used to calculate work-function of the material.

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Optoelectronic properties Semi-local [Reference]

Incident photon energy dependence of optical is shown below [Source-code]. Only interband optical transitions are taken into account.Please note the underestimatation of band-gap problem with DFT will reflect in the spectra as well. For very accurate optical properties GW/BSE calculation would be needed, which is yet to be done because of their very high computational cost. Optical properties for mono-/multi-layer materials were rescaled with the actual thickness to simulation z-box ratio. Absorption coeffiecient is in cm-1 unit. Also, ionic contributions were neglected.

Dense k-mesh based bandgap is : 2.0782 eV

Static real-parts of dielectric function in x,y,z: 5.49,5.51,5.4

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Optoelectronic properties METAGGA-MBJ [Reference]

Single point DFT calculation was carried out with meta-gga MBJ potential [Source-code]. This should give reasonable bandgap, and optical properties assuming the calculation was properly converged. Incident photon energy dependence of optical is shown below. Only interband optical transitions are taken into account. Also, ionic contributions were neglected.

MBJ bandgap is : 2.9737 eV

Static real-parts of dielectric function in x,y,z: 4.45,4.46,4.4

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Solar-cell SLME [Reference]

Theoretical solar-cell efficiency (in %) was calculated using spectroscopy limited maximum efficiency (SLME) and TBmBJ for the material with 500 nm thickness and at 300 K. Note that generally there are many factors that contribute towards the efficiency, such as carrier effective mass etc.

SLME is: 0.39

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Finite-difference: elastic tensor and derived phonon properties [Reference]

Elastic tensor calculated for the conventional cell of the system with finite-difference method [Source-code]. For bulk structures, elastic constants are given in GPa unit . For layered materials, the elastic constants are rescaled with respect to vacuum padding (see the input files) and the units for elastic coefficients are in N/m . Phonons obtained [Source-code] from this calculation are also shown.

WARNING: Please note we provide finite-size cell phonons only. At least 1.2 nm x1.2 nm x1.2 nm size cell or more is generally needed for obtaining reliable phonon spectrum, but we take conventional cell of the structure only. For systems having primitive-cell phonon representation tables, I denotes infrared activity and R denotes Raman active modes (where applicabale). Selection of particular q-point mesh can give rise to unphysical negative modes in phonon density of states and phonon bandstructre. The minimum thermal conductivity was calculated using elastic tensor information following Clarke and Cahill formalism.

Voigt-bulk modulus (K_V): 126.06 GPa, Voigt-shear modulus (G_V): 8.57 GPa

Reuss-bulk modulus (K_R): 125.57 GPa, Reuss-shear modulus (G_R): 230.7 GPa

Poisson's ratio: 0.14, Elastic anisotropy parameter: -4.81

Clarke's lower limit of thermal conductivity (W/(m.K)): 1.16

Cahill's lower limit of thermal conductivity (W/(m.K)): 1.26

Point group

point_group_type: -3

Visualize Phonons here

Phonon mode (cm-1)	Representation
-0.08
-0.0842718077
-0.08
-0.0759281255
-0.01
-0.0104925202
28.01
28.0107392783
93.79
93.7899140147
97.85
97.8549243526
114.07
114.066308259
116.18
116.17763033
142.56
142.562611892
150.89
150.893964134
160.24
160.236963788
203.45
203.447989603
253.33
253.328749833
284.52
284.520942469
297.97
297.965923518
312.16
312.160009479
338.36
338.359153172
492.45
492.450219798
501.44
501.438439927
518.3
518.302990884
656.51
656.505188201

n-& p-type Seebeck coeff. (µV/K), power-factor (µW/(mK²)), conductivity (1/(Ω*m)), zT (assuming lattice part of thermal conductivity as 1 W/(mK)) at 600K and 10²⁰ cm^-3 doping. For mono/multi-layer materials consider Seebeck-coeff only.)