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Structure info
Layer group p-3m1
Layer group number 72
Structure origin original03-18
ICSD id of parent bulk structure ICSD 84217
Stability
Energy above convex hull [eV/atom] 0.000
Heat of formation [eV/atom] -0.166
Dynamically stable Yes
Basic properties
Magnetic No
Band gap (PBE) [eV] 1.787
Band gap (HSE06) [eV] 3.359
XYZ CIF JSON
Axis x [Å] y [Å] z [Å] Periodic
1 4.177 0.000 0.000 Yes
2 -2.088 3.617 0.000 Yes
3 0.000 0.000 18.856 No
Lengths [Å] 4.177 4.177 18.856
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 Cu2I2
Stoichiometry AB
Number of atoms 4
Unit cell area [Å2] 15.110
Thickness [Å] 3.856

Cu2I2 (2CuI-1)
Heat of formation [eV/atom] -0.17
Energy above convex hull [eV/atom] 0.00
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/1/phonon_bs.png
Minimum eigenvalue of Hessian [eV/Ų] -0.00

DVB [eV] xx yy xy
Γ -2.19 -2.29 0.00
M -1.10 -1.87 0.66
K -0.26 -0.37 0.00
kVBM -2.19 -2.29 0.00
xx yy xy
Band gap [eV] 0.86 0.89 -0.00
DCB [eV] xx yy xy
Γ -1.33 -1.40 0.00
M 0.87 -1.50 2.01
K 2.74 2.62 0.00
kCBM -1.33 -1.40 0.00

Cij (N/m) xx yy xy
xx 38.10 16.09 0.00
yy 16.18 38.21 0.00
xy -0.00 0.00 23.44
Stiffness tensor eigenvalues
Eigenvalue 0 22.02 N/m
Eigenvalue 1 23.44 N/m
Eigenvalue 2 54.29 N/m

cij [e/Å] xx yy xy
x -0.00 -0.00 -0.00
y -0.00 0.00 0.00
z 0.00 0.00 -0.00
cijclamped [e/Å] xx yy xy
x 0.00 0.00 -0.00
y -0.00 0.00 -0.00
z 0.00 0.00 0.00

Key values [eV]
Band gap (PBE) 1.787
Direct band gap (PBE) 1.787
Valence band maximum wrt. vacuum (PBE) -4.540
Conduction band minimum wrt. vacuum (PBE) -2.753
DOS BZ

Key values [eV]
Band gap (HSE06) 3.359
Direct band gap (HSE06) 3.359
Valence band maximum wrt. vacuum (HSE06) -5.793
Conduction band minimum wrt. vacuum (HSE06) -2.434

VBM
Property (VBM) Value
Min eff. mass 0.49 m0
Max eff. mass 0.49 m0
DOS eff. mass 0.49 m0
Crystal coordinates [0.000, 0.000]
Warping parameter -0.000
Barrier height > 84.9 meV
Distance to barrier > 0.0173 Å-1
CBM
Property (CBM) Value
Min eff. mass 0.35 m0
Max eff. mass 0.35 m0
DOS eff. mass 0.35 m0
Crystal coordinates [0.000, 0.000]
Warping parameter 0.000
Barrier height > 122.9 meV
Distance to barrier > 0.0173 Å-1

ZIij ux uy uz
Px -1.08 -0.00 0.00
Py -0.00 -1.08 -0.00
Pz 0.00 0.00 -0.24
ZCuij ux uy uz
Px 1.08 0.00 -0.00
Py 0.00 1.08 0.00
Pz 0.00 -0.00 0.24
ZIij ux uy uz
Px -1.08 -0.00 0.00
Py -0.00 -1.08 -0.00
Pz -0.00 0.00 -0.24
ZCuij ux uy uz
Px 1.08 0.00 -0.00
Py 0.00 1.08 0.00
Pz 0.00 -0.00 0.24

Atom No. Chemical symbol Charges [|e|]
0 I -0.30
1 I -0.30
2 Cu 0.30
3 Cu 0.30

AB/2CuI/1/rpa-pol-x.png AB/2CuI/1/rpa-pol-z.png
AB/2CuI/1/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 2.601
Interband polarizability (y) [Å] 2.594
Interband polarizability (z) [Å] 0.462
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000

AB/2CuI/1/ir-pol-x.png AB/2CuI/1/ir-pol-z.png
AB/2CuI/1/ir-pol-y.png
Static polarizability [Å]
Phonons only (x) 2.37
Phonons only (y) 2.37
Phonons only (z) 0.03
Total (phonons + electrons) (x) 4.97
Total (phonons + electrons) (y) 4.96
Total (phonons + electrons) (z) 0.49

AB/2CuI/1/shg1.png AB/2CuI/1/shg3.png AB/2CuI/1/shg5.png
AB/2CuI/1/shg2.png AB/2CuI/1/shg4.png
Element Relations
xxz xxz=xzx=yyz=yzy
yyy yyy=-xxy=-yxx=-xyx
Others 0=xxx=xyy=xyz=xzy=xzz=yxy=yxz=yyx=yzx=yzz=zxy=zxz= zyx=zyz=zzx=zzy
zxx zxx=zyy
zzz

AB/2CuI/1/Raman.png
Mode Frequency (1/cm) Degeneracy
Mode 1 18.4 2
Mode 2 0. 3
Mode 3 67.6 2
Mode 4 92.3 1
Mode 5 101.8 2
Mode 6 149. 1
Mode 7 173.1 1

Miscellaneous details
Unique ID 2CuI-1
Number of atoms 4
Number of species 2
Formula Cu2I2
Reduced formula CuI
Stoichiometry AB
Unit cell area [Å2] 15.110
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/AB/CuI/Cu2I2-ac7333c6ab94
Old uid Cu2I2-ac7333c6ab94
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] 3.856
Structure origin original03-18
Band gap (PBE) [eV] 1.787
Direct band gap (PBE) [eV] 1.787
gap_dir_nosoc 2.043
Vacuum level [eV] 3.466
Fermi level wrt. vacuum (PBE) [eV] -3.646
Valence band maximum wrt. vacuum (PBE) [eV] -4.540
Conduction band minimum wrt. vacuum (PBE) [eV] -2.753
minhessianeig -0.000
Miscellaneous details
Dynamically stable Yes
Band gap (HSE06) [eV] 3.359
Direct band gap (HSE06) [eV] 3.359
Fermi level wrt. vacuum (HSE) [eV] -4.113
Valence band maximum wrt. vacuum (HSE06) [eV] -5.793
Conduction band minimum wrt. vacuum (HSE06) [eV] -2.434
Interband polarizability (x) [Å] 2.601
Interband polarizability (y) [Å] 2.594
Interband polarizability (z) [Å] 0.462
Static polarizability (phonons) (x) [Å] 2.368
Static polarizability (phonons + electrons) (x) [Å] 4.969
Static polarizability (phonons) (y) [Å] 2.367
Static polarizability (phonons + electrons) (y) [Å] 4.961
Static polarizability (phonons) (z) [Å] 0.025
Static polarizability (phonons + electrons) (z) [Å] 0.487
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000
Energy [eV] -10.974
ICSD id of parent bulk structure ICSD 84217
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] 0.000
Heat of formation [eV/atom] -0.166