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Structure info
Layer group p-3m1
Layer group number 72
Structure origin original03-18
Stability
Energy above convex hull [eV/atom] 0.323
Heat of formation [eV/atom] -0.723
Dynamically stable Yes
Basic properties
Magnetic No
Band gap (PBE) [eV] 0.000
XYZ CIF JSON
Axis x [Å] y [Å] z [Å] Periodic
1 3.950 0.000 0.000 Yes
2 -1.975 3.421 0.000 Yes
3 -0.000 0.000 18.856 No
Lengths [Å] 3.950 3.950 18.856
Angles [°] 90.000 90.000 119.998

Symmetries
2D Bravais type Hexagonal (hp)
Layer group number 72
Layer group p-3m1
Space group number (bulk in AA-stacking) 164
Space group (bulk in AA-stacking) P-3m1
Point group -3m
Inversion symmetry Yes
Structure data
Formula Nb2S2
Stoichiometry AB
Number of atoms 4
Unit cell area [Å2] 13.511
Thickness [Å] 3.450

Nb2S2 (2NbS-2)
Heat of formation [eV/atom] -0.72
Energy above convex hull [eV/atom] 0.32
Monolayers from C2DB
Nb7S12 (1Nb7S12-1) -1.17 eV/atom
Nb8S12 (4Nb2S3-1) -1.17 eV/atom
Nb9S12 (3Nb3S4-1) -1.13 eV/atom
Nb7S12 (1Nb7S12-2) -1.10 eV/atom
NbS2 (1NbS2-1) -1.08 eV/atom
Nb4S6 (2Nb2S3-1) -1.05 eV/atom
NbS2 (1NbS2-2) -1.05 eV/atom
Nb8S12 (4Nb2S3-2) -1.05 eV/atom
Nb4S12 (4NbS3-1) -0.82 eV/atom
Nb4S12 (4NbS3-2) -0.82 eV/atom
Nb2S6 (2NbS3-1) -0.80 eV/atom
Nb2S2 (2NbS-1) -0.77 eV/atom
Nb2S2, (2NbS-2) -0.72 eV/atom
S2Nb4 (2SNb2-1) -0.69 eV/atom
NbS2 (1NbS2-3) -0.68 eV/atom
Nb2S2 (2NbS-3) -0.64 eV/atom
Nb2S2 (2NbS-4) -0.57 eV/atom
Nb2S2 (2NbS-5) -0.49 eV/atom
Nb2S2 (2NbS-6) -0.47 eV/atom
S2 (2S-1) 0.45 eV/atom
S2 (2S-2) 0.62 eV/atom
Bulk crystals from OQMD123
Nb6S8 -1.18 eV/atom
NbS2 -1.08 eV/atom
Nb4S12 -0.81 eV/atom
Nb21S8 -0.61 eV/atom
Nb 0.00 eV/atom
S48 0.00 eV/atom

AB/2NbS/2/phonon_bs.png
Minimum eigenvalue of Hessian [eV/Ų] -0.00

Cij (N/m) xx yy xy
xx 83.86 78.16 -0.02
yy 77.96 83.81 -0.03
xy -0.00 -0.00 6.56
Stiffness tensor eigenvalues
Eigenvalue 0 5.78 N/m
Eigenvalue 1 6.56 N/m
Eigenvalue 2 161.89 N/m

Key values [eV]
Band gap (PBE) 0.000
Direct band gap (PBE) 0.000
Fermi level wrt. vacuum (PBE) -3.843
DOS BZ

AB/2NbS/2/fermi_surface.png

Atom No. Chemical symbol Charges [|e|]
0 S -1.06
1 S -1.06
2 Nb 1.06
3 Nb 1.06

AB/2NbS/2/rpa-pol-x.png AB/2NbS/2/rpa-pol-z.png
AB/2NbS/2/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 12.810
Interband polarizability (y) [Å] 13.061
Interband polarizability (z) [Å] 0.381
Plasma frequency (x) [eV Å0.5] 4.558
Plasma frequency (y) [eV Å0.5] 4.581

AB/2NbS/2/Raman.png
Mode Frequency (1/cm) Degeneracy
Mode 1 0. 3
Mode 2 125.6 2
Mode 3 269.9 1
Mode 4 325.2 1
Mode 5 339. 2
Mode 6 364.3 1
Mode 7 382.5 2

Miscellaneous details
Unique ID 2NbS-2
Number of atoms 4
Number of species 2
Formula Nb2S2
Reduced formula NbS
Stoichiometry AB
Unit cell area [Å2] 13.511
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/AB/NbS/Nb2S2-31254123feb9
Old uid Nb2S2-31254123feb9
Space group (bulk in AA-stacking) P-3m1
Space group number (bulk in AA-stacking) 164
Point group -3m
Inversion symmetry Yes
Layer group number 72
Layer group p-3m1
2D Bravais type Hexagonal (hp)
Thickness [Å] 3.450
Structure origin original03-18
Band gap (PBE) [eV] 0.000
Miscellaneous details
Direct band gap (PBE) [eV] 0.000
gap_dir_nosoc 0.000
Vacuum level [eV] 3.994
Fermi level wrt. vacuum (PBE) [eV] -3.843
minhessianeig -0.000
Dynamically stable Yes
Interband polarizability (x) [Å] 12.810
Interband polarizability (y) [Å] 13.061
Interband polarizability (z) [Å] 0.381
Plasma frequency (x) [eV Å0.5] 4.558
Plasma frequency (y) [eV Å0.5] 4.581
Energy [eV] -31.700
Magnetic No
Spin axis z
Magnetic anisotropy energy, xz [meV/unit cell] 0.000
Magnetic anisotropy energy, yz [meV/unit cell] 0.000
Energy above convex hull [eV/atom] 0.323
Heat of formation [eV/atom] -0.723