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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] 0.009
Heat of formation [eV/atom] -0.338
Dynamically stable Yes
Basic properties
Magnetic No
Band gap (PBE) [eV] 1.724
Band gap (HSE06) [eV] 2.962
XYZ CIF JSON
Axis x [Å] y [Å] z [Å] Periodic
1 4.434 -0.000 0.000 Yes
2 -2.217 3.845 0.000 Yes
3 0.000 0.000 18.856 No
Lengths [Å] 4.434 4.438 18.856
Angles [°] 90.000 90.000 119.969

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 Ag2Br2
Stoichiometry AB
Number of atoms 4
Unit cell area [Å2] 17.048
Thickness [Å] 3.841

Ag2Br2 (2AgBr-1)
Heat of formation [eV/atom] -0.34
Energy above convex hull [eV/atom] 0.01
Monolayers from C2DB
Ag4Br4 (4AgBr-1) -0.35 eV/atom
Ag4Br4 (4AgBr-2) -0.34 eV/atom
Ag6Br6 (6AgBr-1) -0.34 eV/atom
Ag2Br2, (2AgBr-1) -0.34 eV/atom
Ag2Br2 (2AgBr-2) -0.34 eV/atom
Ag6Br6 (6AgBr-2) -0.34 eV/atom
Ag6Br6 (6AgBr-3) -0.33 eV/atom
Ag2Br2 (2AgBr-3) -0.33 eV/atom
Ag5Br5 (5AgBr-1) -0.33 eV/atom
Ag6Br6 (6AgBr-4) -0.32 eV/atom
Ag8Br8 (8AgBr-1) -0.32 eV/atom
Ag12Br12 (12AgBr-1) -0.32 eV/atom
Ag3Br3 (3AgBr-1) -0.32 eV/atom
Ag2Br2 (2AgBr-4) -0.31 eV/atom
Ag3Br3 (3AgBr-2) -0.31 eV/atom
Ag3Br3 (3AgBr-3) -0.31 eV/atom
Ag2Br2 (2AgBr-5) -0.30 eV/atom
Ag3Br3 (3AgBr-4) -0.30 eV/atom
Ag8Br8 (8AgBr-2) -0.30 eV/atom
Ag8Br8 (8AgBr-3) -0.30 eV/atom
Ag6Br6 (6AgBr-5) -0.30 eV/atom
AgBr (1AgBr-1) -0.30 eV/atom
Ag2Br2 (2AgBr-6) -0.29 eV/atom
Ag2Br4 (2AgBr2-1) -0.24 eV/atom
Ag4Br8 (4AgBr2-1) -0.24 eV/atom
Ag6Br12 (6AgBr2-1) -0.23 eV/atom
Ag2Br4 (2AgBr2-2) -0.20 eV/atom
AgBr2 (1AgBr2-1) -0.19 eV/atom
Ag2Br6 (2AgBr3-1) -0.19 eV/atom
Ag2Br6 (2AgBr3-2) -0.19 eV/atom
Ag4Br8 (4AgBr2-2) -0.19 eV/atom
Ag2Br6 (2AgBr3-3) -0.18 eV/atom
Ag4Br12 (4AgBr3-1) -0.16 eV/atom
AgBr3 (1AgBr3-1) -0.16 eV/atom
Ag2Br6 (2AgBr3-4) -0.15 eV/atom
AgBr2 (1AgBr2-2) -0.13 eV/atom
AgBr2 (1AgBr2-3) -0.09 eV/atom
Ag2Br6 (2AgBr3-5) -0.06 eV/atom
Ag2Br6 (2AgBr3-6) 0.01 eV/atom
Ag2 (2Ag-1) 0.31 eV/atom
Bulk crystals from OQMD123
AgBr -0.32 eV/atom
Ag4Br6 -0.28 eV/atom
Ag4 0.00 eV/atom
Br4 0.00 eV/atom

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

DVB [eV] xx yy xy
Γ 0.72 0.73 0.01
X -1.63 -1.50 0.00
A1 -1.63 -1.49 0.01
Y -1.46 -0.89 -0.10
kVBM 0.72 0.73 0.01
xx yy xy
Band gap [eV] 0.90 1.02 0.00
DCB [eV] xx yy xy
Γ 1.62 1.75 0.01
X 1.87 2.09 0.03
A1 1.85 2.11 0.04
Y 2.95 2.09 0.93
kCBM 1.62 1.75 0.01

Cij (N/m) xx yy xy
xx 13.53 9.94 -0.20
yy 9.88 12.74 -0.01
xy 0.03 -0.00 6.84
Stiffness tensor eigenvalues
Eigenvalue 0 3.22 N/m
Eigenvalue 1 6.84 N/m
Eigenvalue 2 23.06 N/m

Key values [eV]
Band gap (PBE) 1.724
Direct band gap (PBE) 1.724
Valence band maximum wrt. vacuum (PBE) -6.237
Conduction band minimum wrt. vacuum (PBE) -4.513
DOS BZ

Key values [eV]
Band gap (HSE06) 2.962
Direct band gap (HSE06) 2.962
Valence band maximum wrt. vacuum (HSE06) -7.230
Conduction band minimum wrt. vacuum (HSE06) -4.268

VBM
Property (VBM) Value
Min eff. mass 0.84 m0
Max eff. mass 0.88 m0
DOS eff. mass 0.86 m0
Crystal coordinates [0.000, -0.000]
Warping parameter -0.000
Barrier height > 41.4 meV
Distance to barrier > 0.0163 Å-1
CBM
Property (CBM) Value
Min eff. mass 0.44 m0
Max eff. mass 0.44 m0
DOS eff. mass 0.44 m0
Crystal coordinates [0.000, 0.000]
Warping parameter 0.000
Barrier height > 88.4 meV
Distance to barrier > 0.0163 Å-1

ZBrij ux uy uz
Px -1.31 -0.00 0.00
Py -0.00 -1.31 -0.00
Pz 0.00 -0.00 -0.35
ZAgij ux uy uz
Px 1.31 0.00 -0.00
Py 0.00 1.31 0.00
Pz -0.00 0.00 0.35
ZBrij ux uy uz
Px -1.31 -0.00 0.00
Py -0.00 -1.31 -0.00
Pz 0.00 -0.00 -0.35
ZAgij ux uy uz
Px 1.31 0.00 -0.00
Py 0.00 1.31 0.00
Pz -0.00 0.00 0.35

Atom No. Chemical symbol Charges [|e|]
0 Br -0.41
1 Br -0.40
2 Ag 0.40
3 Ag 0.40

AB/2AgBr/1/rpa-pol-x.png AB/2AgBr/1/rpa-pol-z.png
AB/2AgBr/1/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 1.712
Interband polarizability (y) [Å] 1.711
Interband polarizability (z) [Å] 0.400
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000

AB/2AgBr/1/ir-pol-x.png AB/2AgBr/1/ir-pol-z.png
AB/2AgBr/1/ir-pol-y.png
Static polarizability [Å]
Phonons only (x) 2.52
Phonons only (y) 2.48
Phonons only (z) 0.08
Total (phonons + electrons) (x) 4.23
Total (phonons + electrons) (y) 4.19
Total (phonons + electrons) (z) 0.48

AB/2AgBr/1/Raman.png
Mode Frequency (1/cm) Degeneracy
Mode 1 0.1 3
Mode 2 10.2 1
Mode 3 12.8 1
Mode 4 60.3 1
Mode 5 92.1 1
Mode 6 94.3 1
Mode 7 113.7 1
Mode 8 115.8 1
Mode 9 124.5 1
Mode 10 135.2 1

Miscellaneous details
Unique ID 2AgBr-1
Number of atoms 4
Number of species 2
Formula Ag2Br2
Reduced formula AgBr
Stoichiometry AB
Unit cell area [Å2] 17.048
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/AB/AgBr/Ag2Br2-9d25bdce5cb7
Old uid Ag2Br2-9d25bdce5cb7
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] 3.841
Structure origin original03-18
Band gap (PBE) [eV] 1.724
Direct band gap (PBE) [eV] 1.724
gap_dir_nosoc 1.828
Vacuum level [eV] 2.918
Fermi level wrt. vacuum (PBE) [eV] -5.375
Valence band maximum wrt. vacuum (PBE) [eV] -6.237
Conduction band minimum wrt. vacuum (PBE) [eV] -4.513
Miscellaneous details
minhessianeig -0.000
Dynamically stable Yes
Band gap (HSE06) [eV] 2.962
Direct band gap (HSE06) [eV] 2.962
Fermi level wrt. vacuum (HSE) [eV] -5.749
Valence band maximum wrt. vacuum (HSE06) [eV] -7.230
Conduction band minimum wrt. vacuum (HSE06) [eV] -4.268
Interband polarizability (x) [Å] 1.712
Interband polarizability (y) [Å] 1.711
Interband polarizability (z) [Å] 0.400
Static polarizability (phonons) (x) [Å] 2.516
Static polarizability (phonons + electrons) (x) [Å] 4.228
Static polarizability (phonons) (y) [Å] 2.475
Static polarizability (phonons + electrons) (y) [Å] 4.186
Static polarizability (phonons) (z) [Å] 0.078
Static polarizability (phonons + electrons) (z) [Å] 0.479
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000
Energy [eV] -10.202
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] 0.009
Heat of formation [eV/atom] -0.338