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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] 0.056
Heat of formation [eV/atom] -0.086
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 3.763 -0.000 0.000 Yes
2 -1.881 3.260 0.000 Yes
3 -0.000 0.000 18.856 No
Lengths [Å] 3.763 3.764 18.856
Angles [°] 90.000 90.000 119.992

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 Cu2Se2
Stoichiometry AB
Number of atoms 4
Unit cell area [Å2] 12.267
Thickness [Å] 3.561

Cu2Se2 (2CuSe-1)
Heat of formation [eV/atom] -0.09
Energy above convex hull [eV/atom] 0.06
Monolayers from C2DB
Se2Cu3 (1Se2Cu3-1) -0.11 eV/atom
Se2Cu4 (2SeCu2-1) -0.11 eV/atom
Cu2Se2, (2CuSe-1) -0.09 eV/atom
Cu2Se2 (2CuSe-2) -0.08 eV/atom
Cu2Se2 (2CuSe-3) -0.07 eV/atom
Se5Cu6 (1Se5Cu6-1) -0.07 eV/atom
Se2Cu4 (2SeCu2-2) -0.04 eV/atom
Cu2Se2 (2CuSe-4) -0.04 eV/atom
Cu2Se4 (2CuSe2-1) -0.00 eV/atom
Cu2Se2 (2CuSe-5) 0.02 eV/atom
CuSe2 (1CuSe2-1) 0.03 eV/atom
Cu2Se4 (2CuSe2-2) 0.10 eV/atom
CuSe2 (1CuSe2-2) 0.12 eV/atom
Cu2Se2 (2CuSe-6) 0.12 eV/atom
SeCu2 (1SeCu2-1) 0.14 eV/atom
CuSe2 (1CuSe2-3) 0.17 eV/atom
Se2 (2Se-1) 0.21 eV/atom
Se2 (2Se-2) 0.29 eV/atom
Bulk crystals from OQMD123
Cu6Se4 -0.15 eV/atom
Cu6Se6 -0.14 eV/atom
Cu2Se4 -0.10 eV/atom
Cu 0.00 eV/atom
Se3 0.00 eV/atom

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

Cij (N/m) xx yy xy
xx 37.73 21.13 -0.02
yy 19.95 37.23 0.01
xy -0.05 0.02 19.63
Stiffness tensor eigenvalues
Eigenvalue 0 16.94 N/m
Eigenvalue 1 19.63 N/m
Eigenvalue 2 58.01 N/m

Key values [eV]
Band gap (PBE) 0.000
Direct band gap (PBE) 0.000
Fermi level wrt. vacuum (PBE) -5.586
DOS BZ

AB/2CuSe/1/fermi_surface.png

Atom No. Chemical symbol Charges [|e|]
0 Se -0.36
1 Se -0.36
2 Cu 0.36
3 Cu 0.36

AB/2CuSe/1/rpa-pol-x.png AB/2CuSe/1/rpa-pol-z.png
AB/2CuSe/1/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 115.512
Interband polarizability (y) [Å] 118.588
Interband polarizability (z) [Å] 0.668
Plasma frequency (x) [eV Å0.5] 8.174
Plasma frequency (y) [eV Å0.5] 8.205

AB/2CuSe/1/Raman.png
Mode Frequency (1/cm) Degeneracy
Mode 1 0. 3
Mode 2 87.3 2
Mode 3 156.3 1
Mode 4 165.2 1
Mode 5 190.1 2
Mode 6 202.5 3

Miscellaneous details
Unique ID 2CuSe-1
Number of atoms 4
Number of species 2
Formula Cu2Se2
Reduced formula CuSe
Stoichiometry AB
Unit cell area [Å2] 12.267
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/AB/CuSe/Cu2Se2-9a926e9a5ca9
Old uid Cu2Se2-9a926e9a5ca9
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] 3.561
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] 3.639
Fermi level wrt. vacuum (PBE) [eV] -5.586
minhessianeig -0.000
Dynamically stable Yes
Interband polarizability (x) [Å] 115.512
Interband polarizability (y) [Å] 118.588
Interband polarizability (z) [Å] 0.668
Plasma frequency (x) [eV Å0.5] 8.174
Plasma frequency (y) [eV Å0.5] 8.205
Energy [eV] -14.660
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] 0.056
Heat of formation [eV/atom] -0.086