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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 5000219
Mono/few-layer report(s) 10.1088/2053-1583/ab64fb
Stability
Energy above convex hull [eV/atom] 0.005
Heat of formation [eV/atom] 0.005
Dynamically stable Yes
Basic properties
Magnetic No
Band gap (PBE) [eV] 1.483
Band gap (HSE06) [eV] 2.019
  XYZ CIF JSON
Axis x [Å] y [Å] z [Å] Periodic
1 3.608 -0.000 0.000 Yes
2 -1.804 3.124 0.000 Yes
3 0.000 0.000 15.459 No
Lengths [Å] 3.608 3.608 15.459
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 As2
Stoichiometry A
Number of atoms 2
Unit cell area [Å2] 11.271
Thickness [Å] 1.396

As2 (2As-1)
Heat of formation [eV/atom] 0.01
Energy above convex hull [eV/atom] 0.01
Monolayers from C2DB
As2, (2As-1) 0.01 eV/atom
As4 (4As-1) 0.04 eV/atom
Bulk crystals from OQMD123
As2 0.00 eV/atom

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

DVB [eV] xx yy xy
Γ -6.38 -6.35 -0.00
M 1.35 2.12 -0.86
K 1.26 1.26 -0.00
kVBM -6.38 -6.35 -0.00
xx yy xy
Band gap [eV] -0.03 9.89 0.00
DCB [eV] xx yy xy
Γ -10.63 -10.65 0.00
M -0.26 -6.89 5.83
K 2.79 2.79 -0.00
kCBM -6.40 3.53 -0.00

Cij (N/m) xx yy xy
xx 52.51 8.50 -0.00
yy 8.48 52.47 0.00
xy -0.00 -0.00 43.03
Stiffness tensor eigenvalues
Eigenvalue 0 43.03 N/m
Eigenvalue 1 44.00 N/m
Eigenvalue 2 60.98 N/m

Key values [eV]
Band gap (PBE) 1.483
Direct band gap (PBE) 1.805
Valence band maximum wrt. vacuum (PBE) -5.242
Conduction band minimum wrt. vacuum (PBE) -3.759
DOS BZ

Key values [eV]
Band gap (HSE06) 2.019
Direct band gap (HSE06) 2.451
Valence band maximum wrt. vacuum (HSE06) -5.556
Conduction band minimum wrt. vacuum (HSE06) -3.537

VBM
Property (VBM) Value
Min eff. mass 0.16 m0
Max eff. mass 0.16 m0
DOS eff. mass 0.16 m0
Crystal coordinates [0.000, 0.000]
Warping parameter -0.000
Barrier height > 210.1 meV
Distance to barrier > 0.02 Å-1
CBM
Property (CBM) Value
Min eff. mass 0.13 m0
Max eff. mass 0.50 m0
DOS eff. mass 0.25 m0
Crystal coordinates [0.311, 0.000]
Warping parameter 0.010
Barrier height > 96.5 meV
Distance to barrier > 0.0202 Å-1

ZAsij ux uy uz
Px -0.00 0.00 0.00
Py -0.00 -0.00 -0.00
Pz 0.00 0.00 0.00
ZAsij ux uy uz
Px -0.00 0.00 0.00
Py -0.00 -0.00 -0.00
Pz 0.00 0.00 0.00

Atom No. Chemical symbol Charges [|e|]
0 As -0.00
1 As 0.00

A/2As/1/rpa-pol-x.png A/2As/1/rpa-pol-z.png
A/2As/1/rpa-pol-y.png
Properties
Interband polarizability (x) [Å] 4.331
Interband polarizability (y) [Å] 4.331
Interband polarizability (z) [Å] 0.300
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000

A/2As/1/ir-pol-x.png A/2As/1/ir-pol-z.png
A/2As/1/ir-pol-y.png
Static polarizability [Å]
Phonons only (x) 0.00
Phonons only (y) 0.00
Phonons only (z) 0.00
Total (phonons + electrons) (x) 4.33
Total (phonons + electrons) (y) 4.33
Total (phonons + electrons) (z) 0.30

A/2As/1/Raman.png
Mode Frequency (1/cm) Degeneracy
Mode 1 0. 3
Mode 2 242.5 2
Mode 3 310.7 1

Miscellaneous details
Unique ID 2As-1
Number of atoms 2
Number of species 1
Formula As2
Reduced formula As
Stoichiometry A
Unit cell area [Å2] 11.271
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree/A/As/As2-2cfe371476fd
Old uid As2-2cfe371476fd
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] 1.396
Structure origin original03-18
Band gap (PBE) [eV] 1.483
Direct band gap (PBE) [eV] 1.805
gap_dir_nosoc 1.945
Vacuum level [eV] 2.811
Fermi level wrt. vacuum (PBE) [eV] -4.500
Valence band maximum wrt. vacuum (PBE) [eV] -5.242
Conduction band minimum wrt. vacuum (PBE) [eV] -3.759
minhessianeig -0.000
Miscellaneous details
Dynamically stable Yes
Band gap (HSE06) [eV] 2.019
Direct band gap (HSE06) [eV] 2.451
Fermi level wrt. vacuum (HSE) [eV] -4.631
Valence band maximum wrt. vacuum (HSE06) [eV] -5.556
Conduction band minimum wrt. vacuum (HSE06) [eV] -3.537
Interband polarizability (x) [Å] 4.331
Interband polarizability (y) [Å] 4.331
Interband polarizability (z) [Å] 0.300
Static polarizability (phonons) (x) [Å] 0.000
Static polarizability (phonons + electrons) (x) [Å] 4.331
Static polarizability (phonons) (y) [Å] 0.000
Static polarizability (phonons + electrons) (y) [Å] 4.331
Static polarizability (phonons) (z) [Å] 0.000
Static polarizability (phonons + electrons) (z) [Å] 0.300
Plasma frequency (x) [eV Å0.5] 0.000
Plasma frequency (y) [eV Å0.5] 0.000
Energy [eV] -9.316
COD id of parent bulk structure COD 5000219
Mono/few-layer report(s) 10.1088/2053-1583/ab64fb
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] 0.005
Heat of formation [eV/atom] 0.005