Atoms: Te₂Tl₂

Structure info
Layer group	p-6m2
Layer group number	78
Structure origin	original03-18

Stability
Energy above convex hull [eV/atom]	0.137
Heat of formation [eV/atom]	-0.089
Dynamically stable	Yes

Basic properties
Magnetic state	NM
Band gap [eV]	0.339
Band gap (HSE06) [eV]	0.681

Repeat: 1234   Download: XYZ CIF JSON

Axis	x [Å]	y [Å]	z [Å]	Periodic
1	4.511	0.000	0.000	Yes
2	-2.256	3.907	0.000	Yes
3	-0.000	0.000	20.661	No

Lengths [Å]	4.511	4.511	20.661
Angles [°]	90.000	90.000	120.000

Convex hull

Te2Tl2 (2TeTl-2)
Heat of formation [eV/atom]	-0.09
Energy above convex hull [eV/atom]	0.14

Monolayers from C2DB
Te2Tl4, (2TeTl2-1)	-0.25 eV/atom
Te2Tl4, (2TeTl2-2)	-0.24 eV/atom
TeTl2, (1TeTl2-1)	-0.20 eV/atom
Te4Tl4, (4TeTl-1)	-0.14 eV/atom
Te2Tl2, (2TeTl-1)	-0.13 eV/atom
Tl2Te3, (1Tl2Te3-1)	-0.12 eV/atom
Tl4Te6, (2Tl2Te3-1)	-0.11 eV/atom
Te2Tl2, (2TeTl-2)	-0.09 eV/atom
Te2Tl2, (2TeTl-3)	-0.09 eV/atom
Te2Tl2, (2TeTl-4)	-0.08 eV/atom
Te2Tl2, (2TeTl-5)	-0.05 eV/atom
Tl2Te5, (1Tl2Te5-1)	-0.03 eV/atom
Tl3Te4, (1Tl3Te4-1)	-0.02 eV/atom
Te2Tl2, (2TeTl-6)	-0.00 eV/atom
Tl2Te3, (1Tl2Te3-2)	0.05 eV/atom
Tl2Te4, (2TlTe2-1)	0.06 eV/atom
Te2, (2Te-1)	0.16 eV/atom
TlTe2, (1TlTe2-1)	0.16 eV/atom
Te2, (2Te-2)	0.29 eV/atom

Bulk crystals from OQMD123
Te6Tl10	-0.26 eV/atom
Te8Tl8	-0.23 eV/atom
TeTl3	-0.19 eV/atom
Te6Tl4	-0.18 eV/atom
Te3	0.00 eV/atom
Tl2	0.00 eV/atom

Stiffness tensor

Cij (N/m)	xx	yy	xy
xx	31.12	8.43	0.00
yy	7.52	31.38	0.00
xy	0.00	0.00	23.28

Stiffness tensor eigenvalues
Eigenvalue 0	23.28 N/m
Eigenvalue 1	23.28 N/m
Eigenvalue 2	39.21 N/m

Phonons

Property	Value
Minimum eigenvalue of Hessian [eV/Ų]	-0.00

Deformation potentials

DVB (eV)	xx	yy	xy
Γ	-1.11	-1.10	-0.00
M	0.58	0.02	0.50
K	0.84	0.86	-0.00
kVBM	-0.76	-0.60	-0.14

	xx	yy	xy
Band Gap	-4.30	-4.40	0.14

DCB (eV)	xx	yy	xy
Γ	-5.06	-5.00	-0.00
M	0.34	-2.31	2.25
K	-0.96	-1.09	0.00
kCBM	-5.06	-5.00	-0.00

Band structure and DOS

Effective masses

Property (VBM)	Value
Min eff. mass	0.98 m0
Max eff. mass	1.04 m0
DOS eff. mass	1.01 m0
Crystal coordinates	[0.054, 0.054]
Warping parameter	-0.000
Barrier height	14.1 meV
Distance to barrier	0.011 Å-1

Property (CBM)	Value
Min eff. mass	0.11 m0
Max eff. mass	0.11 m0
DOS eff. mass	0.11 m0
Crystal coordinates	[0.000, 0.000]
Warping parameter	0.001
Barrier height	> 262.7 meV
Distance to barrier	> 0.016 Å-1

Electronic band structure (HSE06@PBE)

Property	Value
KVP: Band gap (HSE06) [eV]	0.68
KVP: Direct band gap (HSE06) [eV]	0.72
Valence band maximum wrt. vacuum level (HSE06)	-5.50 eV
Conduction band minimum wrt. vacuum level (HSE06)	-4.82 eV

Born charges

ZTlij	ux	uy	uz
Px	2.81	0.00	-0.00
Py	0.00	2.81	0.00
Pz	-0.00	0.00	0.19

ZTeij	ux	uy	uz
Px	-2.81	-0.00	0.00
Py	-0.00	-2.81	-0.00
Pz	0.00	0.00	-0.19

ZTlij	ux	uy	uz
Px	2.81	0.00	0.00
Py	0.00	2.81	-0.00
Pz	0.00	0.00	0.19

ZTeij	ux	uy	uz
Px	-2.81	-0.00	-0.00
Py	-0.00	-2.81	0.00
Pz	-0.00	-0.00	-0.19

Second harmonic generation

Element	Relations
yyy	yyy=-xxy=-yxx=-xyx
Others	0=xxx=xxz=xyy=xyz=xzx=xzy=xzz=yxy=yxz=yyx=yyz=yzx= yzy=yzz=zxx=zxy=zxz=zyx=zyy=zyz=zzx=zzy=zzz

Optical polarizability

Properties
Static interband polarizability at (x) [Å]	7.685
Static interband polarizability at (y) [Å]	7.685
Static interband polarizability at (z) [Å]	0.633
Plasma frequency (x) [Å0.5]	0.000
Plasma frequency (y) [Å0.5]	0.000

Infrared polarizability

Static polarizability	[Å]
Phonons only (x)	3.91
Phonons only (y)	3.91
Phonons only (z)	0.01
Total (phonons + electrons) (x)	11.60
Total (phonons + electrons) (y)	11.60
Total (phonons + electrons) (z)	0.65

Optical absorption (BSE and RPA)

Property	Value
The exciton binding energy from the Bethe–Salpeter equation (BSE) [eV].	0.37

Bader charges

#	Chemical symbol	Charges [|e|]
0	Tl	0.29
1	Tl	0.33
2	Te	-0.31
3	Te	-0.31

Piezoelectric tensor

cij (e/Ådim-1)	xx	yy	xy
x	-0.00	-0.00	-0.02
y	-0.02	0.01	-0.00
z	-0.00	0.00	0.00

cclampedij (e/Ådim-1)	xx	yy	xy
x	-0.00	-0.00	-0.33
y	-0.33	0.33	0.00
z	-0.00	-0.00	0.00

Shift current

Element	Relations
yyy	yyy=-xyx=-yxx=-xxy
Others	0=xxx=xxz=xyy=xyz=xzx=xzy=xzz=yxy=yxz=yyx=yyz=yzx= yzy=yzz=zxx=zxy=zxz=zyx=zyy=zyz=zzx=zzy=zzz

Miscellaneous

Miscellaneous details
Unique ID	2TeTl-2
Number of atoms	4
Number of species	2
Formula	Te2Tl2
Reduced formula	TeTl
Stoichiometry	AB
Unit cell area [Å2]	17.623
Original file-system folder	/home/niflheim2/cmr/C2DB-ASR/tree/AB/TeTl/Te2Tl2-73117163f0e2
Old uid	Te2Tl2-73117163f0e2
Inversion symmetry	No
Layer group	p-6m2
Layer group number	78
Structure origin	original03-18
Band gap [eV]	0.339
gap_dir	0.380
gap_dir_nosoc	0.587
Vacuum level [eV]	3.839
Fermi level [eV]	-1.175
minhessianeig	-0.000
Dynamically stable	Yes
Band gap (HSE06) [eV]	0.681
gap_dir_hse	0.716

Miscellaneous details
vbm_hse	-1.662
cbm_hse	-0.980
E_B	0.367
Static interband polarizability at (x) [Å]	7.685
Static interband polarizability at (y) [Å]	7.685
Static interband polarizability at (z) [Å]	0.633
Static polarizability (phonons) (x) [Å]	3.910
Static polarizability (phonons + electrons) (x) [Å]	11.595
Static polarizability (phonons) (y) [Å]	3.912
Static polarizability (phonons + electrons) (y) [Å]	11.597
Static polarizability (phonons) (z) [Å]	0.015
Static polarizability (phonons + electrons) (z) [Å]	0.648
Plasma frequency (x) [Å0.5]	0.000
Plasma frequency (y) [Å0.5]	0.000
Energy [eV]	-11.763
Magnetic state	NM
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]	0.137
Heat of formation [eV/atom]	-0.089