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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): 0.908I

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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Spin-orbit coupling based spillage [Reference]

Below we show results from spin-orbit coupling (SOC) based spillage calculations using wavefunctions of spin-orbit and non-spin-orbit bandstructure calculations. a) non-SOC band structure and b) SOC band structure, c) non-SOC projected band structure and d) SOC projected band structure, projecting onto highest energy orbital of most electronegative atom in the system (assuming the orbital forms the valence band-maximum). e) Spillage, as a function of momentum, k. f) Table of bandgaps and spillage information. Generally, spillage values greater than 0.5 and indirect gap close to zero indicate topological materials.

Spin-orbit spillage is: 0.032

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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 : 0.903 eV

Static real-parts of dielectric function in x,y,z: 4.79,5.0,5.12

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DFPT: IR-intensity, Piezoelecric and Dielectric tensors [Reference]

Calculations are done using density functional perturbation theory (DFPT) method for non-metallic systems for conventional cell and at Gamma-point in phonon BZ.

Static dielecric-tensor

14.6	0.0	-0.0
0.0	11.46	-0.0
-0.0	-0.0	15.5

Piezoelectric-stress-tensor (C/m²)

0.0	-0.0	0.0	-0.14	0.0	0.0
0.07	0.52	-0.89	0.0	0.0	0.0
0.0	0.0	-0.0	0.0	-0.67	0.0

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Thermoelectric properties [Reference]

Thermoelectric properties are calculated using BoltzTrap code [Source-code]. Electron and hole mass tensors (useful for semiconductors and insulators mainly)are given at 300 K [Source-code]. Following plots show the Seebeck coefficient and ZT factor (eigenvalues of the tensor shown) at 300 K along three different crystallographic directions. Seebeck coefficient and ZT plots can be compared for three different temperatures available through the buttons given below. Generally very high Kpoints are needed for obtaining thermoelectric properties. We assume the Kpoints obtained from above convergence were sufficient [Source-code].

WARNING: Constant relaxation time approximation (10^-14 s) and only electronic contribution to thermal conductivity were utilized for calculating ZT.

Electron mass tensor (m_e unit)

Hole mass tensor (m_e unit)