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Structure info
Layer group c2/m11
Layer group number 18
Structure origin Lyngby22_LDP
Stability
Energy above convex hull [eV/atom] 0.032
Heat of formation [eV/atom] -0.685
Dynamically stable Yes
Basic properties
Magnetic No
Band gap (PBE) [eV] 1.642
Band gap (HSE06) [eV] 2.356
XYZ CIF JSON
Axis x [Å] y [Å] z [Å] Periodic
1 3.788 0.000 0.000 Yes
2 -1.894 5.032 0.000 Yes
3 -0.000 0.000 33.096 No
Lengths [Å] 3.788 5.377 33.096
Angles [°] 90.000 90.000 110.625

Symmetries
2D Bravais type Centered rectangular (oc)
Layer group number 18
Layer group c2/m11
Space group number (bulk in AA-stacking) 12
Space group (bulk in AA-stacking) C2/m
Point group 2/m
Inversion symmetry Yes
Structure data
Formula Se2Al2
Stoichiometry AB
Number of atoms 4
Unit cell area [Å2] 19.060
Thickness [Å] 3.221

Al2Se2 (2AlSe-3)
Heat of formation [eV/atom] -0.69
Energy above convex hull [eV/atom] 0.03
Monolayers from C2DB
Al8Se12 (4Al2Se3-1) -0.86 eV/atom
Al4Se6 (2Al2Se3-1) -0.84 eV/atom
Al4Se6 (2Al2Se3-2) -0.83 eV/atom
Al4Se6 (2Al2Se3-3) -0.81 eV/atom
Al2Se3 (1Al2Se3-1) -0.79 eV/atom
Al6Se9 (3Al2Se3-1) -0.77 eV/atom
Al2Se3 (1Al2Se3-2) -0.77 eV/atom
Al3Se4 (1Al3Se4-1) -0.72 eV/atom
Al2Se2 (2AlSe-1) -0.72 eV/atom
Al2Se2 (2AlSe-2) -0.71 eV/atom
Al2Se2, (2AlSe-3) -0.69 eV/atom
Al2Se5 (1Al2Se5-1) -0.60 eV/atom
Al2Se4 (2AlSe2-1) -0.55 eV/atom
AlSe2 (1AlSe2-1) -0.55 eV/atom
Al2Se2 (2AlSe-4) -0.36 eV/atom
Al2Se4 (2AlSe2-2) -0.31 eV/atom
Al2Se2 (2AlSe-5) -0.14 eV/atom
AlSe4 (1AlSe4-1) -0.13 eV/atom
Se2 (2Se-1) 0.21 eV/atom
Se2 (2Se-2) 0.29 eV/atom
Bulk crystals from OQMD123
Al4Se6 -0.84 eV/atom
Al 0.00 eV/atom
Se3 0.00 eV/atom

AB/2AlSe/3/phonon_bs.png
Minimum eigenvalue of Hessian [eV/Ų] -0.00

DVB [eV] xx yy xy
Γ -7.52 1.40 -0.01
X 0.59 -3.92 -0.38
A1 -1.14 -3.17 1.10
Y -0.52 -3.14 -1.28
kVBM 1.50 -2.63 -0.01
xx yy xy
Band gap [eV] -4.36 1.21 0.00
DCB [eV] xx yy xy
Γ -2.86 -1.41 -0.01
X -1.38 -4.97 0.76
A1 4.06 -0.31 -2.35
Y 2.73 -0.99 1.46
kCBM -2.86 -1.41 -0.01

Cij (N/m) xx yy xy
xx 41.97 1.97 0.04
yy 3.12 38.28 0.01
xy -0.00 -0.00 18.63
Stiffness tensor eigenvalues
Eigenvalue 0 18.63 N/m
Eigenvalue 1 37.03 N/m
Eigenvalue 2 43.22 N/m

Key values [eV]
Band gap (PBE) 1.642
Direct band gap (PBE) 2.584
Valence band maximum wrt. vacuum (PBE) -5.158
Conduction band minimum wrt. vacuum (PBE) -3.516
DOS BZ

Key values [eV]
Band gap (HSE06) 2.356
Direct band gap (HSE06) 3.360
Valence band maximum wrt. vacuum (HSE06) -5.589
Conduction band minimum wrt. vacuum (HSE06) -3.233

VBM
Property (VBM) Value
Min eff. mass 0.45 m0
Max eff. mass 3.05 m0
DOS eff. mass 1.17 m0
Crystal coordinates [0.097, 0.452]
Warping parameter -0.000
Barrier height > 8.1 meV
Distance to barrier > 0.0176 Å-1
CBM
Property (CBM) Value
Min eff. mass 0.29 m0
Max eff. mass 0.37 m0
DOS eff. mass 0.33 m0
Crystal coordinates [0.000, 0.000]
Warping parameter 0.002
Barrier height > 120.5 meV
Distance to barrier > 0.0176 Å-1

ZSeij ux uy uz
Px -2.20 -0.00 -0.00
Py -0.00 -1.94 0.15
Pz 0.00 0.04 -0.24
ZAlij ux uy uz
Px 2.20 0.00 0.00
Py -0.00 1.94 -0.15
Pz 0.00 -0.04 0.24
ZSeij ux uy uz
Px -2.20 -0.00 -0.00
Py -0.00 -1.94 0.15
Pz 0.00 0.04 -0.24
ZAlij ux uy uz
Px 2.20 0.00 0.00
Py 0.00 1.94 -0.15
Pz -0.00 -0.04 0.24

Atom No. Chemical symbol Charges [|e|]
0 Se -1.43
1 Se -1.43
2 Al 1.48
3 Al 1.38

Miscellaneous details
Unique ID 2AlSe-3
Number of atoms 4
Number of species 2
Formula Se2Al2
Reduced formula SeAl
Stoichiometry AB
Unit cell area [Å2] 19.060
Original file-system folder /home/niflheim2/cmr/C2DB-ASR/tree_LDP/AB/AlSe/Al2Se2-22f91230bb3e
Old uid Al2Se2-812d7e985061
Space group (bulk in AA-stacking) C2/m
Space group number (bulk in AA-stacking) 12
Point group 2/m
Inversion symmetry Yes
Layer group number 18
Layer group c2/m11
2D Bravais type Centered rectangular (oc)
Thickness [Å] 3.221
Structure origin Lyngby22_LDP
Band gap (PBE) [eV] 1.642
Direct band gap (PBE) [eV] 2.584
Miscellaneous details
gap_dir_nosoc 2.598
Vacuum level [eV] 1.464
Fermi level wrt. vacuum (PBE) [eV] -4.337
Valence band maximum wrt. vacuum (PBE) [eV] -5.158
Conduction band minimum wrt. vacuum (PBE) [eV] -3.516
minhessianeig -0.000
Dynamically stable Yes
Band gap (HSE06) [eV] 2.356
Direct band gap (HSE06) [eV] 3.360
Fermi level wrt. vacuum (HSE) [eV] -4.411
Valence band maximum wrt. vacuum (HSE06) [eV] -5.589
Conduction band minimum wrt. vacuum (HSE06) [eV] -3.233
Energy [eV] -17.183
Magnetic No
Total magnetic moment [μB] 0.000
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] 0.032
Heat of formation [eV/atom] -0.685