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Structure info
Layer group p-3m1
Layer group number 72
Structure origin original03-18
COD id of parent bulk structure COD 2105342
Stability
Energy above convex hull [eV/atom] 0.010
Heat of formation [eV/atom] -0.259
Dynamically stable Yes
Basic properties
Magnetic No
Band gap (PBE) [eV] 1.768
Band gap (HSE06) [eV] 2.782
XYZ CIF JSON
Axis x [Å] y [Å] z [Å] Periodic
1 4.575 0.000 0.000 Yes
2 -2.287 3.967 0.000 Yes
3 0.000 0.000 18.856 No
Lengths [Å] 4.575 4.579 18.856
Angles [°] 90.000 90.000 119.970

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 Ag2I2
Stoichiometry AB
Number of atoms 4
Unit cell area [Å2] 18.149
Thickness [Å] 4.147

Ag2I2 (2AgI-1)
Heat of formation [eV/atom] -0.26
Energy above convex hull [eV/atom] 0.01
Monolayers from C2DB
Ag2I2, (2AgI-1) -0.26 eV/atom
Ag2I2 (2AgI-2) -0.25 eV/atom
Ag6I6 (6AgI-1) -0.24 eV/atom
Ag5I5 (5AgI-1) -0.24 eV/atom
Ag6I6 (6AgI-2) -0.23 eV/atom
Ag2I2 (2AgI-3) -0.22 eV/atom
Ag6I6 (6AgI-3) -0.22 eV/atom
Ag6I6 (6AgI-4) -0.21 eV/atom
Ag3I3 (3AgI-1) -0.21 eV/atom
Ag3I3 (3AgI-2) -0.21 eV/atom
AgI (1AgI-1) -0.20 eV/atom
Ag2I2 (2AgI-4) -0.19 eV/atom
Ag6I8 (2Ag3I4-1) -0.19 eV/atom
I12Ag15 (3I4Ag5-1) -0.17 eV/atom
Ag6I12 (6AgI2-1) -0.16 eV/atom
Ag3I5 (1Ag3I5-1) -0.14 eV/atom
Ag2I6 (2AgI3-1) -0.13 eV/atom
Ag4I8 (4AgI2-1) -0.12 eV/atom
Ag2I4 (2AgI2-1) -0.12 eV/atom
Ag2I6 (2AgI3-2) -0.11 eV/atom
Ag4I8 (4AgI2-2) -0.10 eV/atom
Ag4I12 (4AgI3-1) -0.09 eV/atom
Ag2I4 (2AgI2-2) -0.08 eV/atom
AgI3 (1AgI3-1) -0.07 eV/atom
AgI2 (1AgI2-1) -0.06 eV/atom
AgI2 (1AgI2-2) -0.06 eV/atom
AgI2 (1AgI2-3) 0.03 eV/atom
Ag2I6 (2AgI3-3) 0.07 eV/atom
Ag2I6 (2AgI3-4) 0.07 eV/atom
Ag2 (2Ag-1) 0.31 eV/atom
Bulk crystals from OQMD123
AgI -0.27 eV/atom
Ag4 0.00 eV/atom
I4 0.00 eV/atom

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

DVB [eV] xx yy xy
Γ -1.76 -1.75 0.18
X -1.04 -1.08 0.23
A1 -1.04 -1.08 0.23
Y -1.38 -2.07 0.81
kVBM -1.76 -1.75 0.18
xx yy xy
Band gap [eV] 1.56 1.49 0.01
DCB [eV] xx yy xy
Γ -0.20 -0.26 0.18
X 0.28 0.22 0.23
A1 0.29 0.22 0.22
Y 1.42 -0.23 1.60
kCBM -0.20 -0.26 0.18

Cij (N/m) xx yy xy
xx 19.69 10.49 -0.07
yy 10.33 19.70 -0.00
xy -0.05 -0.07 9.85
Stiffness tensor eigenvalues
Eigenvalue 0 9.29 N/m
Eigenvalue 1 9.85 N/m
Eigenvalue 2 30.10 N/m

Key values [eV]
Band gap (PBE) 1.768
Direct band gap (PBE) 1.768
Valence band maximum wrt. vacuum (PBE) -5.415
Conduction band minimum wrt. vacuum (PBE) -3.646
DOS BZ

Key values [eV]
Band gap (HSE06) 2.782
Direct band gap (HSE06) 2.782
Valence band maximum wrt. vacuum (HSE06) -6.157
Conduction band minimum wrt. vacuum (HSE06) -3.375

VBM
Property (VBM) Value
Min eff. mass 0.51 m0
Max eff. mass 0.51 m0
DOS eff. mass 0.51 m0
Crystal coordinates [0.000, -0.000]
Warping parameter -0.000
Barrier height > 69.1 meV
Distance to barrier > 0.0158 Å-1
CBM
Property (CBM) Value
Min eff. mass 0.39 m0
Max eff. mass 0.39 m0
DOS eff. mass 0.39 m0
Crystal coordinates [0.000, 0.000]
Warping parameter 0.000
Barrier height > 93.5 meV
Distance to barrier > 0.0158 Å-1

ZIij ux uy uz
Px -1.24 -0.00 0.00
Py -0.00 -1.24 -0.00
Pz 0.00 0.00 -0.31
ZAgij ux uy uz
Px 1.24 0.00 -0.00
Py 0.00 1.24 0.00
Pz -0.00 -0.00 0.31
ZIij ux uy uz
Px -1.24 -0.00 0.00
Py -0.00 -1.24 -0.00
Pz 0.00 0.00 -0.31
ZAgij ux uy uz
Px 1.24 0.00 -0.00
Py 0.00 1.24 0.00
Pz -0.00 0.00 0.31

Atom No. Chemical symbol Charges [|e|]
0 I -0.26
1 I -0.26
2 Ag 0.26
3 Ag 0.26

AB/2AgI/1/rpa-pol-x.png AB/2AgI/1/rpa-pol-z.png
AB/2AgI/1/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 2.183
Interband polarizability (y) [Å] 2.181
Interband polarizability (z) [Å] 0.461
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000

AB/2AgI/1/ir-pol-x.png AB/2AgI/1/ir-pol-z.png
AB/2AgI/1/ir-pol-y.png
Static polarizability [Å]
Phonons only (x) 2.47
Phonons only (y) 2.46
Phonons only (z) 0.05
Total (phonons + electrons) (x) 4.66
Total (phonons + electrons) (y) 4.64
Total (phonons + electrons) (z) 0.51

AB/2AgI/1/Raman.png
Mode Frequency (1/cm) Degeneracy
Mode 1 0.1 3
Mode 2 16. 2
Mode 3 70.6 1
Mode 4 76.6 2
Mode 5 96.5 2
Mode 6 112.3 1
Mode 7 130.8 1

Miscellaneous details
Unique ID 2AgI-1
Number of atoms 4
Number of species 2
Formula Ag2I2
Reduced formula AgI
Stoichiometry AB
Unit cell area [Å2] 18.149
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/AB/AgI/Ag2I2-0c52f79478e2
Old uid Ag2I2-0c52f79478e2
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] 4.147
Structure origin original03-18
Band gap (PBE) [eV] 1.768
Direct band gap (PBE) [eV] 1.768
gap_dir_nosoc 2.069
Vacuum level [eV] 3.342
Fermi level wrt. vacuum (PBE) [eV] -4.531
Valence band maximum wrt. vacuum (PBE) [eV] -5.415
Conduction band minimum wrt. vacuum (PBE) [eV] -3.646
minhessianeig -0.000
Miscellaneous details
Dynamically stable Yes
Band gap (HSE06) [eV] 2.782
Direct band gap (HSE06) [eV] 2.782
Fermi level wrt. vacuum (HSE) [eV] -4.766
Valence band maximum wrt. vacuum (HSE06) [eV] -6.157
Conduction band minimum wrt. vacuum (HSE06) [eV] -3.375
Interband polarizability (x) [Å] 2.183
Interband polarizability (y) [Å] 2.181
Interband polarizability (z) [Å] 0.461
Static polarizability (phonons) (x) [Å] 2.473
Static polarizability (phonons + electrons) (x) [Å] 4.657
Static polarizability (phonons) (y) [Å] 2.458
Static polarizability (phonons + electrons) (y) [Å] 4.639
Static polarizability (phonons) (z) [Å] 0.048
Static polarizability (phonons + electrons) (z) [Å] 0.510
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000
Energy [eV] -9.672
COD id of parent bulk structure COD 2105342
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] 0.010
Heat of formation [eV/atom] -0.259