C2DB-logo

Structure info
Layer group p-3m1
Layer group number 72
Structure origin original03-18
COD id of parent bulk structure COD 1538603
ICSD id of parent bulk structure ICSD 645379
Stability
Energy above convex hull [eV/atom] 0.033
Heat of formation [eV/atom] -0.845
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 3.481 0.000 0.000 Yes
2 -1.741 3.015 0.000 Yes
3 -0.000 0.000 18.366 No
Lengths [Å] 3.481 3.481 18.366
Angles [°] 90.000 90.000 120.000

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 NbSe2
Stoichiometry AB2
Number of atoms 3
Unit cell area [Å2] 10.496
Thickness [Å] 3.338

NbSe2 (1NbSe2-2)
Heat of formation [eV/atom] -0.85
Energy above convex hull [eV/atom] 0.03
Monolayers from C2DB
Nb7Se12 (1Nb7Se12-1) -0.90 eV/atom
Nb8Se12 (4Nb2Se3-1) -0.88 eV/atom
NbSe2 (1NbSe2-1) -0.88 eV/atom
Nb4Se6 (2Nb2Se3-1) -0.87 eV/atom
Nb7Se12 (1Nb7Se12-2) -0.85 eV/atom
NbSe2, (1NbSe2-2) -0.85 eV/atom
Nb9Se12 (3Nb3Se4-1) -0.82 eV/atom
Nb8Se12 (4Nb2Se3-2) -0.80 eV/atom
Nb9Se12 (3Nb3Se4-2) -0.75 eV/atom
Nb4Se12 (4NbSe3-1) -0.70 eV/atom
Nb2Se6 (2NbSe3-1) -0.67 eV/atom
Se2Nb4 (2SeNb2-1) -0.55 eV/atom
Nb2Se2 (2NbSe-1) -0.53 eV/atom
Nb2Se2 (2NbSe-2) -0.51 eV/atom
Nb2Se2 (2NbSe-3) -0.46 eV/atom
NbSe2 (1NbSe2-3) -0.44 eV/atom
Nb2Se2 (2NbSe-4) -0.25 eV/atom
Nb2Se2 (2NbSe-5) -0.23 eV/atom
Se2 (2Se-1) 0.21 eV/atom
Se2 (2Se-2) 0.29 eV/atom
Bulk crystals from OQMD123
Nb6Se8 -0.91 eV/atom
Nb4Se8 -0.88 eV/atom
Nb6Se18 -0.69 eV/atom
Nb8Se4 -0.55 eV/atom
Nb4Se18 -0.54 eV/atom
Nb 0.00 eV/atom
Se3 0.00 eV/atom

AB2/1NbSe2/2/phonon_bs.png
Minimum eigenvalue of Hessian [eV/Ų] -0.00

Cij (N/m) xx yy xy
xx 71.67 12.89 -0.02
yy 12.41 71.49 -0.02
xy 0.00 0.00 58.90
Stiffness tensor eigenvalues
Eigenvalue 0 58.90 N/m
Eigenvalue 1 58.94 N/m
Eigenvalue 2 84.23 N/m

Key values [eV]
Band gap (PBE) 0.000
Direct band gap (PBE) 0.000
Fermi level wrt. vacuum (PBE) -4.902
DOS BZ

AB2/1NbSe2/2/fermi_surface.png

Atom No. Chemical symbol Charges [|e|]
0 Nb 1.43
1 Se -0.72
2 Se -0.72

AB2/1NbSe2/2/rpa-pol-x.png AB2/1NbSe2/2/rpa-pol-z.png
AB2/1NbSe2/2/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 26.587
Interband polarizability (y) [Å] 26.587
Interband polarizability (z) [Å] 0.407
Plasma frequency (x) [eV Å0.5] 7.865
Plasma frequency (y) [eV Å0.5] 7.865

AB2/1NbSe2/2/Raman.png
Mode Frequency (1/cm) Degeneracy
Mode 1 0. 3
Mode 2 145.9 2
Mode 3 168.5 2
Mode 4 211.5 1
Mode 5 305.6 1

Miscellaneous details
Unique ID 1NbSe2-2
Number of atoms 3
Number of species 2
Formula NbSe2
Reduced formula NbSe2
Stoichiometry AB2
Unit cell area [Å2] 10.496
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/AB2/NbSe2/NbSe2-7c30b3de2c08
Old uid NbSe2-7c30b3de2c08
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] 3.338
Structure origin original03-18
Band gap (PBE) [eV] 0.000
Direct band gap (PBE) [eV] 0.000
Miscellaneous details
gap_dir_nosoc 0.000
Vacuum level [eV] 4.265
Fermi level wrt. vacuum (PBE) [eV] -4.902
minhessianeig -0.000
Dynamically stable Yes
Interband polarizability (x) [Å] 26.587
Interband polarizability (y) [Å] 26.587
Interband polarizability (z) [Å] 0.407
Plasma frequency (x) [eV Å0.5] 7.865
Plasma frequency (y) [eV Å0.5] 7.865
Energy [eV] -19.828
ICSD id of parent bulk structure ICSD 645379
COD id of parent bulk structure COD 1538603
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] 0.033
Heat of formation [eV/atom] -0.845