Overview: Al₈Se₁₂

Structure info
Layer group	p2_1/b11
Layer group number	17
Structure origin	Lyngby22_LDP

Stability
Energy above convex hull [eV/atom]	0.000
Heat of formation [eV/atom]	-0.857
Dynamically stable	Yes

Basic properties
Magnetic	No
Band gap (PBE) [eV]	2.654
Band gap (HSE06) [eV]	3.600

Repeat: 1234   Download: XYZ CIF JSON

Axis	x [Å]	y [Å]	z [Å]	Periodic
1	6.723	-0.000	0.000	Yes
2	-0.000	12.214	0.000	Yes
3	-0.000	-0.000	34.230	No

Lengths [Å]	6.723	12.214	34.230
Angles [°]	90.000	90.000	90.003

Crystal structure

Symmetries
2D Bravais type	Rectangular (op)
Layer group number	17
Layer group	p2_1/b11
Space group number (bulk in AA-stacking)	14
Space group (bulk in AA-stacking)	P2_1/c
Point group	2/m
Inversion symmetry	Yes

Structure data
Formula	Se12Al8
Stoichiometry	A2B3
Number of atoms	20
Unit cell area [Å2]	82.110
Thickness [Å]	3.776

Stability

Convex hull

Al8Se12 (4Al2Se3-1)
Heat of formation [eV/atom]	-0.86
Energy above convex hull [eV/atom]	0.00

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

Phonons

Minimum eigenvalue of Hessian [eV/Ų]

-0.00

Linear deformations

Stiffness tensor

Cij (N/m)	xx	yy	xy
xx	41.99	4.04	0.00
yy	5.72	14.74	-0.00
xy	0.00	0.00	29.87

Stiffness tensor eigenvalues
Eigenvalue 0	13.92 N/m
Eigenvalue 1	29.87 N/m
Eigenvalue 2	42.82 N/m

Electronic bands

Band structure and DOS

Key values [eV]
Band gap (PBE)	2.654
Direct band gap (PBE)	2.654
Valence band maximum wrt. vacuum (PBE)	-5.719
Conduction band minimum wrt. vacuum (PBE)	-3.065

Electronic band structure (HSE06@PBE)

Key values [eV]
Band gap (HSE06)	3.600
Direct band gap (HSE06)	3.600
Valence band maximum wrt. vacuum (HSE06)	-6.341
Conduction band minimum wrt. vacuum (HSE06)	-2.741

Effective masses

Property (VBM)	Value
Min eff. mass	0.36 m0
Max eff. mass	∞
DOS eff. mass	∞
Crystal coordinates	[0.010, 0.002]
Warping parameter	-0.190
Barrier height	> 1.8 meV
Distance to barrier	> 0.00958 Å-1

Property (CBM)	Value
Min eff. mass	0.27 m0
Max eff. mass	0.30 m0
DOS eff. mass	0.28 m0
Crystal coordinates	[0.000, -0.000]
Warping parameter	0.001
Barrier height	> 42.4 meV
Distance to barrier	> 0.0093 Å-1

Electronic properties

Born charges

ZAlij	ux	uy	uz
Px	2.56	0.18	-0.24
Py	-0.14	2.38	-0.96
Pz	-0.04	-0.10	0.39

ZAlij	ux	uy	uz
Px	2.42	-0.33	0.31
Py	0.13	2.40	-0.82
Pz	0.04	-0.09	0.35

ZAlij	ux	uy	uz
Px	2.56	-0.18	-0.24
Py	0.14	2.38	0.96
Pz	-0.04	0.10	0.39

ZAlij	ux	uy	uz
Px	2.42	-0.33	0.31
Py	0.13	2.40	-0.82
Pz	0.04	-0.09	0.35

ZSeij	ux	uy	uz
Px	-2.18	0.11	0.04
Py	-0.13	-2.07	0.03
Pz	0.01	0.01	-0.17

ZSeij	ux	uy	uz
Px	-1.14	-0.27	0.00
Py	-0.22	-1.52	0.43
Pz	0.00	0.05	-0.29

ZSeij	ux	uy	uz
Px	-1.66	-0.46	-0.11
Py	-0.52	-1.18	0.41
Pz	-0.02	0.04	-0.28

ZSeij	ux	uy	uz
Px	-1.14	0.27	0.00
Py	0.22	-1.52	-0.43
Pz	0.00	-0.05	-0.29

ZSeij	ux	uy	uz
Px	-2.18	-0.11	0.04
Py	0.13	-2.07	-0.03
Pz	0.01	-0.01	-0.17

ZSeij	ux	uy	uz
Px	-1.66	-0.46	-0.11
Py	-0.52	-1.18	0.41
Pz	-0.02	0.04	-0.28

ZAlij	ux	uy	uz
Px	2.56	-0.18	-0.24
Py	0.14	2.38	0.96
Pz	-0.04	0.10	0.39

ZAlij	ux	uy	uz
Px	2.42	0.33	0.31
Py	-0.13	2.40	0.82
Pz	0.04	0.09	0.35

ZAlij	ux	uy	uz
Px	2.56	0.18	-0.24
Py	-0.14	2.38	-0.96
Pz	-0.04	-0.10	0.39

ZAlij	ux	uy	uz
Px	2.42	0.33	0.31
Py	-0.13	2.40	0.82
Pz	0.04	0.09	0.35

ZSeij	ux	uy	uz
Px	-2.18	-0.11	0.04
Py	0.13	-2.07	-0.03
Pz	0.01	-0.01	-0.17

ZSeij	ux	uy	uz
Px	-1.14	0.27	0.00
Py	0.22	-1.52	-0.43
Pz	0.00	-0.05	-0.29

ZSeij	ux	uy	uz
Px	-1.66	0.46	-0.11
Py	0.52	-1.18	-0.41
Pz	-0.02	-0.04	-0.28

ZSeij	ux	uy	uz
Px	-1.14	-0.27	0.00
Py	-0.22	-1.52	0.43
Pz	0.00	0.05	-0.29

ZSeij	ux	uy	uz
Px	-2.18	0.11	0.04
Py	-0.13	-2.07	0.03
Pz	0.01	0.01	-0.17

ZSeij	ux	uy	uz
Px	-1.66	0.46	-0.11
Py	0.52	-1.18	-0.41
Pz	-0.02	-0.04	-0.28

Miscellaneous

Miscellaneous details
Unique ID	4Al2Se3-1
Number of atoms	20
Number of species	2
Formula	Se12Al8
Reduced formula	Se3Al2
Stoichiometry	A2B3
Unit cell area [Å2]	82.110
Original file-system folder	/home/niflheim2/cmr/C2DB-ASR/tree_LDP/A2B3/Al2Se3/Al8Se12-6c058e0a0e29
Old uid	Al8Se12-40697c675594
Space group (bulk in AA-stacking)	P2_1/c
Space group number (bulk in AA-stacking)	14
Point group	2/m
Inversion symmetry	Yes
Layer group number	17
Layer group	p2_1/b11
2D Bravais type	Rectangular (op)
Thickness [Å]	3.776
Structure origin	Lyngby22_LDP
Band gap (PBE) [eV]	2.654
Direct band gap (PBE) [eV]	2.654

Miscellaneous details
gap_dir_nosoc	2.667
Vacuum level [eV]	1.659
Fermi level wrt. vacuum (PBE) [eV]	-4.392
Valence band maximum wrt. vacuum (PBE) [eV]	-5.719
Conduction band minimum wrt. vacuum (PBE) [eV]	-3.065
minhessianeig	-0.000
Dynamically stable	Yes
Band gap (HSE06) [eV]	3.600
Direct band gap (HSE06) [eV]	3.600
Fermi level wrt. vacuum (HSE) [eV]	-4.541
Valence band maximum wrt. vacuum (HSE06) [eV]	-6.341
Conduction band minimum wrt. vacuum (HSE06) [eV]	-2.741
Energy [eV]	-88.833
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]	0.000
Heat of formation [eV/atom]	-0.857