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Structure info
Layer group p4/nmm
Layer group number 64
Structure origin original03-18
COD id of parent bulk structure COD 9013924
Stability
Energy above convex hull [eV/atom] 0.008
Heat of formation [eV/atom] -0.158
Dynamically stable No
Basic properties
Magnetic No
Band gap (PBE) [eV] 1.865
Band gap (HSE06) [eV] 3.552
Band gap (G₀W₀) [eV] 3.504
XYZ CIF JSON
Axis x [Å] y [Å] z [Å] Periodic
1 4.115 -0.000 0.000 Yes
2 0.000 4.115 0.000 Yes
3 -0.000 0.000 18.833 No
Lengths [Å] 4.115 4.115 18.833
Angles [°] 90.000 90.000 90.000

Symmetries
2D Bravais type Square (tp)
Layer group number 64
Layer group p4/nmm
Space group number (bulk in AA-stacking) 129
Space group (bulk in AA-stacking) P4/nmm
Point group 4/mmm
Inversion symmetry Yes
Structure data
Formula Cu2I2
Stoichiometry AB
Number of atoms 4
Unit cell area [Å2] 16.933
Thickness [Å] 3.441

Cu2I2 (2CuI-2)
Heat of formation [eV/atom] -0.16
Energy above convex hull [eV/atom] 0.01
Monolayers from C2DB
Cu2I2 (2CuI-1) -0.17 eV/atom
Cu2I2, (2CuI-2) -0.16 eV/atom
Cu3I3 (3CuI-1) -0.15 eV/atom
Cu5I5 (5CuI-1) -0.14 eV/atom
Cu6I6 (6CuI-1) -0.14 eV/atom
Cu4I4 (4CuI-1) -0.13 eV/atom
CuI2 (1CuI2-1) -0.13 eV/atom
Cu2I3 (1Cu2I3-1) -0.12 eV/atom
Cu4I6 (2Cu2I3-1) -0.12 eV/atom
Cu3I6 (3CuI2-1) -0.11 eV/atom
Cu9I11 (1Cu9I11-1) -0.10 eV/atom
Cu6I6 (6CuI-2) -0.10 eV/atom
Cu3I3 (3CuI-2) -0.10 eV/atom
Cu6I6 (6CuI-3) -0.10 eV/atom
Cu3I3 (3CuI-3) -0.10 eV/atom
Cu3I3 (3CuI-4) -0.09 eV/atom
Cu2I4 (2CuI2-1) -0.09 eV/atom
Cu3I5 (1Cu3I5-1) -0.09 eV/atom
Cu4I4 (4CuI-2) -0.09 eV/atom
CuI (1CuI-1) -0.08 eV/atom
Cu4I8 (4CuI2-1) -0.08 eV/atom
Cu4I8 (4CuI2-2) -0.08 eV/atom
Cu3I4 (1Cu3I4-1) -0.07 eV/atom
Cu2I4 (2CuI2-2) -0.06 eV/atom
Cu4I6 (2Cu2I3-2) -0.05 eV/atom
CuI2 (1CuI2-2) -0.05 eV/atom
Cu2I5 (1Cu2I5-1) -0.03 eV/atom
Cu2I6 (2CuI3-1) 0.05 eV/atom
CuI2 (1CuI2-3) 0.09 eV/atom
Cu2I6 (2CuI3-2) 0.10 eV/atom
Bulk crystals from OQMD123
CuI -0.16 eV/atom
Cu 0.00 eV/atom
I4 0.00 eV/atom

AB/2CuI/2/phonon_bs.png
Minimum eigenvalue of Hessian [eV/Ų] -0.19

Cij (N/m) xx yy xy
xx 32.66 -0.79 -0.00
yy -1.59 32.91 -0.00
xy 0.00 0.00 -3.28
Stiffness tensor eigenvalues
Eigenvalue 0 -3.28 N/m
Eigenvalue 1 31.66 N/m
Eigenvalue 2 33.91 N/m

Key values [eV]
Band gap (PBE) 1.865
Direct band gap (PBE) 1.865
Valence band maximum wrt. vacuum (PBE) -4.570
Conduction band minimum wrt. vacuum (PBE) -2.705
DOS BZ

Key values [eV]
Band gap (HSE06) 3.552
Direct band gap (HSE06) 3.552
Valence band maximum wrt. vacuum (HSE06) -5.924
Conduction band minimum wrt. vacuum (HSE06) -2.372

Key values [eV]
Band gap (G₀W₀) 3.504
Direct band gap (G₀W₀) 3.504
Valence band maximum wrt. vacuum (G₀W₀) -5.626
Conduction band minimum wrt. vacuum (G₀W₀) -2.122

VBM
Property (VBM) Value
Min eff. mass 0.58 m0
Max eff. mass 0.59 m0
DOS eff. mass 0.58 m0
Crystal coordinates [0.000, -0.000]
Warping parameter -0.008
Barrier height > 47.6 meV
Distance to barrier > 0.0152 Å-1
CBM
Property (CBM) Value
Min eff. mass 0.30 m0
Max eff. mass 0.31 m0
DOS eff. mass 0.30 m0
Crystal coordinates [-0.000, 0.000]
Warping parameter 0.003
Barrier height > 93.3 meV
Distance to barrier > 0.0152 Å-1

Atom No. Chemical symbol Charges [|e|]
0 I -0.32
1 I -0.32
2 Cu 0.32
3 Cu 0.32

AB/2CuI/2/rpa-pol-x.png AB/2CuI/2/rpa-pol-z.png
AB/2CuI/2/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 2.253
Interband polarizability (y) [Å] 2.253
Interband polarizability (z) [Å] 0.421
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000

AB/2CuI/2/absx.png
Exciton binding energy (BSE) [eV] 0.92
AB/2CuI/2/absz.png

Miscellaneous details
Unique ID 2CuI-2
Number of atoms 4
Number of species 2
Formula Cu2I2
Reduced formula CuI
Stoichiometry AB
Unit cell area [Å2] 16.933
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/AB/CuI/Cu2I2-48470661aab1
Old uid Cu2I2-48470661aab1
Space group (bulk in AA-stacking) P4/nmm
Space group number (bulk in AA-stacking) 129
Point group 4/mmm
Inversion symmetry Yes
Layer group number 64
Layer group p4/nmm
2D Bravais type Square (tp)
Thickness [Å] 3.441
Structure origin original03-18
Band gap (PBE) [eV] 1.865
Direct band gap (PBE) [eV] 1.865
gap_dir_nosoc 2.077
Vacuum level [eV] 3.114
Fermi level wrt. vacuum (PBE) [eV] -3.637
Valence band maximum wrt. vacuum (PBE) [eV] -4.570
Conduction band minimum wrt. vacuum (PBE) [eV] -2.705
minhessianeig -0.192
Miscellaneous details
Dynamically stable No
Band gap (HSE06) [eV] 3.552
Direct band gap (HSE06) [eV] 3.552
Fermi level wrt. vacuum (HSE) [eV] -4.148
Valence band maximum wrt. vacuum (HSE06) [eV] -5.924
Conduction band minimum wrt. vacuum (HSE06) [eV] -2.372
Band gap (G₀W₀) [eV] 3.504
Direct band gap (G₀W₀) [eV] 3.504
Fermi level wrt. vacuum (G₀W₀) [eV] -3.874
Valence band maximum wrt. vacuum (G₀W₀) [eV] -5.626
Conduction band minimum wrt. vacuum (G₀W₀) [eV] -2.122
E_B 0.916
Interband polarizability (x) [Å] 2.253
Interband polarizability (y) [Å] 2.253
Interband polarizability (z) [Å] 0.421
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000
Energy [eV] -10.940
COD id of parent bulk structure COD 9013924
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] 0.008
Heat of formation [eV/atom] -0.158