JVASP-13383_Na3CrCl6
JARVIS-ID:JVASP-13383 Functional:optB88-vdW Primitive cell Primitive cell Conventional cell Conventional cell
Chemical formula:Na3CrCl6 Formation energy/atom (eV):-1.609 a 6.782 Å α:90.0 ° a 6.782 Å α:90.0 °
Space-group :P-31c, 163 Relaxed energy/atom (eV):-2.0439 b 6.782 Å β:90.0 ° b 6.782 Å β:90.0 °
Calculation type:Bulk SCF bandgap (eV):1.802 c 11.97 Å γ:120.0 ° c 11.97 Å γ:120.0 °
Crystal system:trigonal Point group:-3m Density (gcm-3):2.32 Volume (3):476.76 nAtoms_prim:20 nAtoms_conv:20
Download input files

Convergence [Reference]

Calculations are done using VASP software [Source-code]. Convergence on KPOINTS [Source-code] and ENCUT [Source-code] is done with respect to total energy of the system within 0.001 eV tolerance. Please note convergence on KPOINTS and ENCUT is generally done for target properties, but here we assume energy-convergence with 0.001 eV should be sufficient for other properties also. The points on the curves are obtained with single-point calculation (number of ionic steps, NSW=1 ). However, for very accurate calculations, NSW>1 might be needed.


Structural analysis [Reference]

The following shows the X-ray diffraction (XRD)[Source-code] pattern and the Radial distribution function (RDF) plots [Source-code]. XRD peaks should be comparable to experiments for bulk structures. Relative intensities may differ. For mono- and multi-layer structures , we take the z-dimension during DFT calculation for XRD calculations, which may differ from the experimental set-up.


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): 1.775I


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.


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 : 0.0082 eV

Static real-parts of dielectric function in x,y,z: 11.07,11.07,8.62


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 (KV): 23.33 GPa, Voigt-shear modulus (GV): 8.94 GPa

Reuss-bulk modulus (KR): 23.25 GPa, Reuss-shear modulus (GR): 8.58 GPa

Poisson's ratio: 0.33, Elastic anisotropy parameter: 0.22

Clarke's lower limit of thermal conductivity (W/(m.K)): 0.46

Cahill's lower limit of thermal conductivity (W/(m.K)): 0.52

Elastic tensor
35.0 20.3 16.3 0.0 -0.0 -1.3
20.3 35.0 16.3 -0.0 0.0 1.3
16.3 16.3 34.2 -0.0 0.0 0.0
-0.0 -0.0 -0.0 7.4 1.3 0.0
-0.0 0.0 0.0 1.3 10.1 -0.0
-1.3 1.3 0.0 0.0 -0.0 10.1

Phonon mode (cm-1)
-0.2
-0.17
-0.17
36.68
50.54
50.54
65.49
66.38
66.38
93.24
94.87
94.87
105.97
124.25
124.25
130.69
132.41
133.58
133.58
134.1
134.1
138.26
138.26
138.68
145.05
145.05
145.88
157.82
157.82
162.14
163.22
173.74
177.57
177.57
180.81
180.81
181.93
181.93
182.84
182.84
201.76
208.49
209.0
213.29
215.19
215.19
218.47
218.47
226.8
226.8
232.67
232.67
253.68
271.19
271.19
271.65
271.65
272.8
284.77
319.2

Point group

point_group_type: 2/m

Visualize Phonons here
Phonon mode (cm-1) Representation
-0.2
-0.2011218748
-0.17
-0.1712773339
-0.17
-0.1683166275
36.68
36.6840563201
50.54
50.5390732434
65.49
65.4937622457
66.38
66.375635709
93.24
93.2421412786
94.87
94.8708270011
105.97
105.973843234
124.25
124.246655967
130.69
130.690632362
132.41
132.407732591
133.58
133.576900327
134.1
134.099623898
138.26
138.260584744
138.68
138.678098438
145.05
145.047157663
145.88
145.884560718
157.82
157.823933771
162.14
162.139810875
163.22
163.222351751
173.74
173.740207344
177.57
177.568040645
180.81
180.811949091
181.93
181.933745778
182.84
182.844671701
201.76
201.756957936
208.49
208.490668406
209.0
209.001167036
213.29
213.288023232
215.19
215.193112889
218.47
218.469909806
226.8
226.7988325
232.67
232.669927847
253.68
253.678435018
271.19
271.191706695
271.65
271.653435407
272.8
272.803277243
284.77
284.770517053
319.2
319.196790563

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 (me unit)

13.22 0.0 0.0
0.0 13.22 -0.0
0.0 -0.0 17.85

Hole mass tensor (me unit)

19.22 0.0 0.0
0.0 19.22 -0.0
0.0 -0.0 174.36

n-& p-type Seebeck coeff. (µV/K), power-factor (µW/(mK2)), conductivity (1/(*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.)

Property xx yy zz
n-Seebeck -339.22 -332.5 -332.5
n-PowerFactor 82.04 113.91 113.91
n-Conductivity 712.95 1030.33 1030.33
n-ZT 0.05 0.07 0.07
p-Seebeck 375.82 375.82 445.74
p-PowerFactor 34.35 111.1 111.1
p-Conductivity 172.88 786.61 786.61
p-ZT 0.02 0.07 0.07

Magnetic moment [Reference]

The orbital magnetic moment was obtained after SCF run. This is not a DFT+U calculation, hence the data could be used to predict zero or non-zero magnetic moment nature of the material only.

Total magnetic moment: 6.0 μB

Magnetic moment per atom: 0.3 μB

Magnetization
Elementsspdtot
Na0.0020.0010.00.002
Na0.0020.0010.00.002
Na0.0010.00.00.001
Na0.0010.00.00.001
Na0.0010.00.00.001
Na0.0010.00.00.001
Cr0.0160.0222.8412.878
Cr0.0160.0222.8412.878
Cl-0.0-0.0150.0-0.015
Cl-0.0-0.0150.0-0.016
Cl-0.0-0.0160.0-0.016
Cl-0.0-0.0140.0-0.014
Cl-0.0-0.0130.0-0.014
Cl-0.0-0.0140.0-0.014
Cl-0.0-0.0150.0-0.016
Cl-0.0-0.0150.0-0.015
Cl-0.0-0.0140.0-0.014
Cl-0.0-0.0160.0-0.016
Cl-0.0-0.0140.0-0.014
Cl-0.0-0.0130.0-0.014

See also

Links to other databases or papers are provided below


mp-28360

ICSD-ID: 62035

AFLOW link

MP link
mp-28360

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