Overview: Bi₄

Structure info
Layer group	pman
Layer group number	42
Structure origin	Lyngby22_LDP

Stability
Energy above convex hull [eV/atom]	0.103
Heat of formation [eV/atom]	0.103
Dynamically stable	No

Basic properties
Magnetic	No
Band gap (PBE) [eV]	0.115

Repeat: 1234   Download: XYZ CIF JSON

Axis	x [Å]	y [Å]	z [Å]	Periodic
1	4.584	0.000	0.000	Yes
2	0.000	5.026	0.000	Yes
3	0.000	0.000	17.110	No

Lengths [Å]	4.584	5.026	17.110
Angles [°]	90.000	90.000	89.997

Crystal structure

Symmetries
2D Bravais type	Rectangular (op)
Layer group number	42
Layer group	pman
Space group number (bulk in AA-stacking)	53
Space group (bulk in AA-stacking)	Pmna
Point group	mmm
Inversion symmetry	Yes

Structure data
Formula	Bi4
Stoichiometry	A
Number of atoms	4
Unit cell area [Å2]	23.037
Thickness [Å]	2.982

Stability

Convex hull

Bi4 (4Bi-2)
Heat of formation [eV/atom]	0.10
Energy above convex hull [eV/atom]	0.10

Monolayers from C2DB
Bi4 (4Bi-1)	0.10 eV/atom
Bi2 (2Bi-1)	0.10 eV/atom
Bi4, (4Bi-2)	0.10 eV/atom

Bulk crystals from OQMD123
Bi2	0.00 eV/atom

Phonons

Minimum eigenvalue of Hessian [eV/Ų]

-0.57

Linear deformations

Stiffness tensor

Cij (N/m)	xx	yy	xy
xx	43.36	18.32	-0.00
yy	19.55	21.35	-0.00
xy	-0.01	-0.01	17.51

Stiffness tensor eigenvalues
Eigenvalue 0	10.46 N/m
Eigenvalue 1	17.51 N/m
Eigenvalue 2	54.25 N/m

Electronic bands

Band structure and DOS

Key values [eV]
Band gap (PBE)	0.115
Direct band gap (PBE)	0.115
Valence band maximum wrt. vacuum (PBE)	-3.753
Conduction band minimum wrt. vacuum (PBE)	-3.639

Effective masses

Property (VBM)	Value
Min eff. mass	0.06 m0
Max eff. mass	0.12 m0
DOS eff. mass	0.08 m0
Crystal coordinates	[-0.219, 0.000]
Warping parameter	-0.015
Barrier height	> 143.9 meV
Distance to barrier	> 0.0182 Å-1

Property (CBM)	Value
Min eff. mass	0.05 m0
Max eff. mass	0.11 m0
DOS eff. mass	0.07 m0
Crystal coordinates	[0.223, 0.000]
Warping parameter	0.013
Barrier height	> 163.2 meV
Distance to barrier	> 0.0182 Å-1

Electronic properties

Bader charges

Atom No.	Chemical symbol	Charges [|e|]
0	Bi	-0.00
1	Bi	0.00
2	Bi	-0.00
3	Bi	0.00

Miscellaneous

Miscellaneous details
Unique ID	4Bi-2
Number of atoms	4
Number of species	1
Formula	Bi4
Reduced formula	Bi
Stoichiometry	A
Unit cell area [Å2]	23.037
Original file-system folder	/home/niflheim2/cmr/C2DB-ASR/tree_LDP/A/Bi/Bi4-6e8bd5b30b55
Old uid	Bi4-00b35729b99c
Space group (bulk in AA-stacking)	Pmna
Space group number (bulk in AA-stacking)	53
Point group	mmm
Inversion symmetry	Yes
Layer group number	42
Layer group	pman
2D Bravais type	Rectangular (op)
Thickness [Å]	2.982
Structure origin	Lyngby22_LDP

Miscellaneous details
Band gap (PBE) [eV]	0.115
Direct band gap (PBE) [eV]	0.115
gap_dir_nosoc	0.390
Vacuum level [eV]	3.524
Fermi level wrt. vacuum (PBE) [eV]	-3.696
Valence band maximum wrt. vacuum (PBE) [eV]	-3.753
Conduction band minimum wrt. vacuum (PBE) [eV]	-3.639
minhessianeig	-0.573
Dynamically stable	No
Energy [eV]	-18.284
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]	0.103
Heat of formation [eV/atom]	0.103