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Structure info
Layer group p4/mmm
Layer group number 61
Structure origin original03-18
Stability
Energy above convex hull [eV/atom] 0.477
Heat of formation [eV/atom] -0.568
Dynamically stable No
Basic properties
Magnetic No
Band gap (PBE) [eV] 0.000
  XYZ CIF JSON
Axis x [Å] y [Å] z [Å] Periodic
1 3.872 -0.000 0.000 Yes
2 0.000 3.873 0.000 Yes
3 -0.000 0.000 17.678 No
Lengths [Å] 3.872 3.873 17.678
Angles [°] 90.000 90.000 90.000

Symmetries
2D Bravais type Square (tp)
Layer group number 61
Layer group p4/mmm
Space group number (bulk in AA-stacking) 123
Space group (bulk in AA-stacking) P4/mmm
Point group 4/mmm
Inversion symmetry Yes
Structure data
Formula Nb2S2
Stoichiometry AB
Number of atoms 4
Unit cell area [Å2] 14.996
Thickness [Å] 3.344

Nb2S2 (2NbS-4)
Heat of formation [eV/atom] -0.57
Energy above convex hull [eV/atom] 0.48
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/4/phonon_bs.png
Minimum eigenvalue of Hessian [eV/Ų] -2.75

Cij (N/m) xx yy xy
xx 81.34 49.58 0.00
yy 49.72 81.32 0.00
xy 0.00 0.00 104.90
Stiffness tensor eigenvalues
Eigenvalue 0 31.67 N/m
Eigenvalue 1 104.90 N/m
Eigenvalue 2 130.98 N/m

Key values [eV]
Band gap (PBE) 0.000
Direct band gap (PBE) 0.000
Fermi level wrt. vacuum (PBE) -5.036
DOS BZ

AB/2NbS/4/fermi_surface.png

Atom No. Chemical symbol Charges [|e|]
0 Nb 0.95
1 S -0.95
2 Nb 0.95
3 S -0.95

AB/2NbS/4/rpa-pol-x.png AB/2NbS/4/rpa-pol-z.png
AB/2NbS/4/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 9.953
Interband polarizability (y) [Å] 10.029
Interband polarizability (z) [Å] 0.408
Plasma frequency (x) [eV Å0.5] 10.488
Plasma frequency (y) [eV Å0.5] 10.490

Miscellaneous details
Unique ID 2NbS-4
Number of atoms 4
Number of species 2
Formula Nb2S2
Reduced formula NbS
Stoichiometry AB
Unit cell area [Å2] 14.996
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/AB/NbS/Nb2S2-58c4219ecbbe
Old uid Nb2S2-58c4219ecbbe
Space group (bulk in AA-stacking) P4/mmm
Space group number (bulk in AA-stacking) 123
Point group 4/mmm
Inversion symmetry Yes
Layer group number 61
Layer group p4/mmm
2D Bravais type Square (tp)
Thickness [Å] 3.344
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] 3.956
Fermi level wrt. vacuum (PBE) [eV] -5.036
minhessianeig -2.753
Dynamically stable No
Interband polarizability (x) [Å] 9.953
Interband polarizability (y) [Å] 10.029
Interband polarizability (z) [Å] 0.408
Plasma frequency (x) [eV Å0.5] 10.488
Plasma frequency (y) [eV Å0.5] 10.490
Energy [eV] -31.082
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] 0.477
Heat of formation [eV/atom] -0.568