Atoms: Ga₂Ge₂Te₂

Structure info
Layer group	p-3m1
Layer group number	72
Structure origin	exfoliated02-21
ICSD id of parent bulk structure	ICSD 35386

Stability
Energy above convex hull [eV/atom]	0.000
Heat of formation [eV/atom]	-0.252
Dynamically stable	Yes

Basic properties
Magnetic state	NM
Band gap [eV]	0.674
Band gap (HSE06) [eV]	1.165

Repeat: 1234   Download: XYZ CIF JSON

Axis	x [Å]	y [Å]	z [Å]	Periodic
1	4.116	0.000	0.000	Yes
2	-2.058	3.565	0.000	Yes
3	0.000	0.000	38.171	No

Lengths [Å]	4.116	4.116	38.171
Angles [°]	90.000	90.000	120.000

Convex hull

Ga2Ge2Te2 (2GaGeTe-1)
Heat of formation [eV/atom]	-0.25
Energy above convex hull [eV/atom]	0.00

Monolayers from C2DB
Ga2Te2, (2GaTe-1)	-0.37 eV/atom
Ga2Te2, (2GaTe-2)	-0.37 eV/atom
Ga8Te12, (4Ga2Te3-1)	-0.33 eV/atom
Ga2Te2, (2GaTe-3)	-0.32 eV/atom
Te12Ga13, (1Te12Ga13-1)	-0.32 eV/atom
Te12Ga14, (2Te6Ga7-1)	-0.27 eV/atom
Ga4Te6, (2Ga2Te3-1)	-0.27 eV/atom
Ga2Ge2Te2, (2GaGeTe-1)	-0.25 eV/atom
Ga2Te5, (1Ga2Te5-1)	-0.25 eV/atom
Ga4Te6, (2Ga2Te3-2)	-0.24 eV/atom
Te12Ga15, (3Te4Ga5-1)	-0.23 eV/atom
Ga3Te4, (1Ga3Te4-1)	-0.22 eV/atom
Ga2Te2, (2GaTe-4)	-0.21 eV/atom
GaTe2, (1GaTe2-1)	-0.18 eV/atom
Ga2Te2, (2GaTe-5)	-0.17 eV/atom
Ga2Ge2Te6, (2GaGeTe3-1)	-0.13 eV/atom
Ga2Te4, (2GaTe2-1)	-0.11 eV/atom
Ga2Te4, (2GaTe2-2)	-0.09 eV/atom
GaGeTe2, (1GaGeTe2-1)	-0.09 eV/atom
Ge2Te2, (2GeTe-1)	-0.04 eV/atom
Ga2Te2, (2GaTe-6)	-0.01 eV/atom
GeTe, (1GeTe-1)	-0.01 eV/atom
Ge2Te2, (2GeTe-2)	-0.00 eV/atom
GaTe4, (1GaTe4-1)	0.05 eV/atom
GeTe2, (1GeTe2-1)	0.07 eV/atom
GeTe2, (1GeTe2-2)	0.08 eV/atom
Ga2Te3, (1Ga2Te3-1)	0.08 eV/atom
GaGeTe3, (1GaGeTe3-1)	0.10 eV/atom
Ga2Te4, (2GaTe2-3)	0.14 eV/atom
Ge2Te4, (2GeTe2-1)	0.14 eV/atom
Te2, (2Te-1)	0.16 eV/atom
Ga4, (4Ga-1)	0.16 eV/atom
GeTe2, (1GeTe2-3)	0.20 eV/atom
Ge2Te4, (2GeTe2-2)	0.27 eV/atom
Te2, (2Te-2)	0.29 eV/atom
Ge2Te2, (2GeTe-3)	0.38 eV/atom
Ge2, (2Ge-1)	0.48 eV/atom
Ge2, (2Ge-2)	0.49 eV/atom

Bulk crystals from OQMD123
Ga6Te6	-0.37 eV/atom
Ga14Te20	-0.34 eV/atom
Ga2Te5	-0.24 eV/atom
GeTe	-0.09 eV/atom
Ga4	0.00 eV/atom
Ge2	0.00 eV/atom
Te3	0.00 eV/atom

Stiffness tensor

Cij (N/m)	xx	yy	xy
xx	96.68	19.55	0.02
yy	19.57	96.64	0.02
xy	-0.00	0.00	78.34

Stiffness tensor eigenvalues
Eigenvalue 0	77.10 N/m
Eigenvalue 1	78.34 N/m
Eigenvalue 2	116.22 N/m

Phonons

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

Deformation potentials

DVB (eV)	xx	yy	xy
Γ	-2.03	-1.99	0.00
M	0.45	-0.03	0.55
K	0.85	0.84	0.00
kVBM	-1.59	-0.11	0.00

	xx	yy	xy
Band Gap	-9.10	-10.61	-0.00

DCB (eV)	xx	yy	xy
Γ	-10.69	-10.72	-0.00
M	0.02	-5.60	5.00
K	0.43	0.42	0.00
kCBM	-10.69	-10.72	-0.00

Band structure and DOS

Effective masses

Property (VBM)	Value
Min eff. mass	0.89 m0
Max eff. mass	1.96 m0
DOS eff. mass	1.32 m0
Crystal coordinates	[0.060, -0.000]
Warping parameter	-0.000
Barrier height	2.2 meV
Distance to barrier	0.00762 Å-1

Property (CBM)	Value
Min eff. mass	0.07 m0
Max eff. mass	0.07 m0
DOS eff. mass	0.07 m0
Crystal coordinates	[0.000, 0.000]
Warping parameter	0.000
Barrier height	> 515.2 meV
Distance to barrier	> 0.0175 Å-1

Electronic band structure (HSE06@PBE)

Property	Value
KVP: Band gap (HSE06) [eV]	1.16
KVP: Direct band gap (HSE06) [eV]	1.17
Valence band maximum wrt. vacuum level (HSE06)	-5.25 eV
Conduction band minimum wrt. vacuum level (HSE06)	-4.08 eV

Born charges

ZGaij	ux	uy	uz
Px	2.27	0.00	0.00
Py	0.00	2.27	-0.00
Pz	0.00	-0.00	0.19

ZGeij	ux	uy	uz
Px	0.09	-0.00	-0.00
Py	-0.00	0.09	0.00
Pz	0.00	0.00	-0.03

ZTeij	ux	uy	uz
Px	-2.35	0.00	-0.00
Py	0.00	-2.35	0.00
Pz	0.00	-0.00	-0.15

ZGaij	ux	uy	uz
Px	2.27	0.00	0.00
Py	0.00	2.27	-0.00
Pz	0.00	-0.00	0.19

ZGeij	ux	uy	uz
Px	0.09	-0.00	-0.00
Py	-0.00	0.09	0.00
Pz	0.00	0.00	-0.03

ZTeij	ux	uy	uz
Px	-2.35	0.00	-0.00
Py	0.00	-2.35	0.00
Pz	0.00	-0.00	-0.15

Optical polarizability

Properties
Static interband polarizability at (x) [Å]	10.645
Static interband polarizability at (y) [Å]	10.645
Static interband polarizability at (z) [Å]	0.815

Infrared polarizability

Static polarizability	[Å]
Phonons only (x)	2.22
Phonons only (y)	2.21
Phonons only (z)	0.01
Total (phonons + electrons) (x)	12.86
Total (phonons + electrons) (y)	12.86
Total (phonons + electrons) (z)	0.82

Bader charges

#	Chemical symbol	Charges [|e|]
0	Ga	0.53
1	Ga	0.53
2	Ge	-0.07
3	Ge	-0.06
4	Te	-0.47
5	Te	-0.47

Miscellaneous

Miscellaneous details
Unique ID	2GaGeTe-1
Number of atoms	6
Number of species	3
Formula	Ga2Ge2Te2
Reduced formula	GaGeTe
Stoichiometry	ABC
Unit cell area [Å2]	14.675
Original file-system folder	/home/niflheim2/cmr/C2DB-ASR/ICSD-COD/3el/Ga6Ge6Te6
Old uid	Ga2Ge2Te2-aeebf5bc1ad7
Inversion symmetry	Yes
Layer group	p-3m1
Layer group number	72
Structure origin	exfoliated02-21
Band gap [eV]	0.674
gap_dir	0.687
gap_dir_nosoc	0.842
Vacuum level [eV]	2.826
Fermi level [eV]	-1.770
minhessianeig	-0.000
Dynamically stable	Yes
Band gap (HSE06) [eV]	1.165

Miscellaneous details
gap_dir_hse	1.169
vbm_hse	-2.421
cbm_hse	-1.256
Static interband polarizability at (x) [Å]	10.645
Static interband polarizability at (y) [Å]	10.645
Static interband polarizability at (z) [Å]	0.815
Static polarizability (phonons) (x) [Å]	2.218
Static polarizability (phonons + electrons) (x) [Å]	12.863
Static polarizability (phonons) (y) [Å]	2.211
Static polarizability (phonons + electrons) (y) [Å]	12.856
Static polarizability (phonons) (z) [Å]	0.008
Static polarizability (phonons + electrons) (z) [Å]	0.823
Energy [eV]	-22.759
ICSD id of parent bulk structure	ICSD 35386
Magnetic state	NM
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]	-0.252