Overview: Ti₂Se₃

Structure info
Layer group	p-6m2
Layer group number	78
Structure origin	Wang23

Stability
Energy above convex hull [eV/atom]	0.069
Heat of formation [eV/atom]	-1.124
Dynamically stable	Yes

Basic properties
Magnetic	Yes
Band gap (PBE) [eV]	0.000

Repeat: 1234   Download: XYZ CIF JSON

Axis	x [Å]	y [Å]	z [Å]	Periodic
1	3.395	1.107	0.000	Yes
2	0.739	3.494	0.000	Yes
3	0.000	0.000	21.368	No

Lengths [Å]	3.571	3.571	21.368
Angles [°]	90.000	90.000	60.001

Crystal structure

Symmetries
2D Bravais type	Hexagonal (hp)
Layer group number	78
Layer group	p-6m2
Space group number (bulk in AA-stacking)	187
Space group (bulk in AA-stacking)	P-6m2
Point group	-6m2
Inversion symmetry	No

Structure data
Formula	Ti2Se3
Stoichiometry	A2B3
Number of atoms	5
Unit cell area [Å2]	11.045
Thickness [Å]	6.368

Stability

Convex hull

Ti2Se3 (1Ti2Se3-1)
Heat of formation [eV/atom]	-1.12
Energy above convex hull [eV/atom]	0.07

Monolayers from C2DB
Ti4Se8 (4TiSe2-1)	-1.13 eV/atom
Ti2Se3, (1Ti2Se3-1)	-1.12 eV/atom
TiSe2 (1TiSe2-1)	-1.12 eV/atom
TiSe2 (1TiSe2-2)	-1.00 eV/atom
Ti2Se2 (2SeTi-1)	-0.87 eV/atom
TiSe2 (1TiSe2-3)	-0.86 eV/atom
Ti2Se2 (2SeTi-2)	-0.83 eV/atom
Ti2Se6 (2TiSe3-1)	-0.83 eV/atom
Ti2Se2 (2SeTi-3)	-0.78 eV/atom
Ti2Se2 (2SeTi-4)	-0.56 eV/atom
Ti2Se2 (2SeTi-5)	-0.55 eV/atom
Se2 (2Se-1)	0.21 eV/atom
Se2 (2Se-2)	0.29 eV/atom

Bulk crystals from OQMD123
Ti6Se8	-1.22 eV/atom
Ti2Se4	-1.12 eV/atom
Ti5Se4	-1.06 eV/atom
Ti24Se12	-0.83 eV/atom
Se3	0.00 eV/atom
Ti3	0.00 eV/atom

Phonons

Minimum eigenvalue of Hessian [eV/Ų]

0.00

Linear deformations

Stiffness tensor

Cij (N/m)	xx	yy	xy
xx	95.80	16.88	0.25
yy	17.55	95.14	0.26
xy	0.02	0.01	78.81

Stiffness tensor eigenvalues
Eigenvalue 0	78.25 N/m
Eigenvalue 1	78.81 N/m
Eigenvalue 2	112.68 N/m

Basic magnetic properties

Total magnetic moment [μB]	1.533
Magnetic anisotropy energy, xz [meV/unit cell]	0.119
Magnetic anisotropy energy, yz [meV/unit cell]	0.119

Atom index	Atom type	Local spin magnetic moment (μB)	Local orbital magnetic moment (μB)
0	Se	-0.009	-0.001
1	Se	-0.009	-0.001
2	Se	-0.025	-0.002
3	Ti	0.611	-0.015
4	Ti	0.609	-0.015

Half-metal gap (PBE) [eV]	0.000
Direct Half-metal gap (PBE) [eV]	0.000

Electronic bands

Band structure and DOS

Key values [eV]
Band gap (PBE)	0.000
Direct band gap (PBE)	0.000
Fermi level wrt. vacuum (PBE)	-5.116

Fermi surface

Electronic properties

Bader charges

Atom No.	Chemical symbol	Charges [|e|]
0	Se	-0.85
1	Se	-0.85
2	Se	-1.22
3	Ti	1.46
4	Ti	1.46

Optical properties

Optical polarizability

Properties
Interband polarizability (x) [Å]	37.163
Interband polarizability (y) [Å]	37.151
Interband polarizability (z) [Å]	0.640
Plasma frequency (x) [eV Å0.5]	5.380
Plasma frequency (y) [eV Å0.5]	5.385

Miscellaneous

Miscellaneous details
Unique ID	1Ti2Se3-1
Number of atoms	5
Number of species	2
Formula	Ti2Se3
Reduced formula	Ti2Se3
Stoichiometry	A2B3
Unit cell area [Å2]	11.045
Original file-system folder	/home/niflheim2/cmr/C2DB-ASR/tree_Wang23/A2B3/Ti2Se3/Ti2Se3-ae8113c4ca01
Old uid	Ti2Se3-22df21778e22
Space group (bulk in AA-stacking)	P-6m2
Space group number (bulk in AA-stacking)	187
Point group	-6m2
Inversion symmetry	No
Layer group number	78
Layer group	p-6m2
2D Bravais type	Hexagonal (hp)
Thickness [Å]	6.368
Structure origin	Wang23
Band gap (PBE) [eV]	0.000
Direct band gap (PBE) [eV]	0.000

Miscellaneous details
gap_dir_nosoc	0.000
Vacuum level [eV]	5.433
Fermi level wrt. vacuum (PBE) [eV]	-5.116
minhessianeig	0.000
Dynamically stable	Yes
Interband polarizability (x) [Å]	37.163
Interband polarizability (y) [Å]	37.151
Interband polarizability (z) [Å]	0.640
Plasma frequency (x) [eV Å0.5]	5.380
Plasma frequency (y) [eV Å0.5]	5.385
Energy [eV]	-29.449
Magnetic	Yes
Total magnetic moment [μB]	1.533
Spin axis	x
Magnetic anisotropy energy, xz [meV/unit cell]	0.119
Magnetic anisotropy energy, yz [meV/unit cell]	0.119
Half-metal gap (PBE) [eV]	0.000
Direct Half-metal gap (PBE) [eV]	0.000
Energy above convex hull [eV/atom]	0.069
Heat of formation [eV/atom]	-1.124