Overview: Nb₂Cl₆

Structure info
Layer group	p-31m
Layer group number	71
Structure origin	original03-18

Stability
Energy above convex hull [eV/atom]	0.117
Heat of formation [eV/atom]	-1.220
Dynamically stable	No

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	5.826	-0.000	0.000	Yes
2	-2.913	5.046	0.000	Yes
3	-0.000	0.000	18.034	No

Lengths [Å]	5.826	5.826	18.034
Angles [°]	90.000	90.000	120.000

Crystal structure

Symmetries
2D Bravais type	Hexagonal (hp)
Layer group number	71
Layer group	p-31m
Space group number (bulk in AA-stacking)	162
Space group (bulk in AA-stacking)	P-31m
Point group	-3m
Inversion symmetry	Yes

Structure data
Formula	Nb2Cl6
Stoichiometry	AB3
Number of atoms	8
Unit cell area [Å2]	29.397
Thickness [Å]	3.024

Stability

Convex hull

Nb2Cl6 (2NbCl3-1)
Heat of formation [eV/atom]	-1.22
Energy above convex hull [eV/atom]	0.12

Monolayers from C2DB
Nb3Cl8 (1Nb3Cl8-1)	-1.35 eV/atom
Nb2Cl6, (2NbCl3-1)	-1.22 eV/atom
Nb2Cl6 (2NbCl3-2)	-1.19 eV/atom
NbCl4 (1NbCl4-1)	-1.16 eV/atom
Nb2Cl4 (2NbCl2-1)	-1.13 eV/atom
NbCl2 (1NbCl2-1)	-1.06 eV/atom
NbCl2 (1NbCl2-2)	-0.96 eV/atom
NbCl2 (1NbCl2-3)	-0.76 eV/atom
Cl2Nb2 (2ClNb-1)	-0.17 eV/atom
Cl2Nb2 (2ClNb-2)	-0.10 eV/atom

Bulk crystals from OQMD123
Cl16Nb6	-1.33 eV/atom
Cl8Nb2	-1.32 eV/atom
Cl28Nb12	-1.31 eV/atom
Cl30Nb6	-1.30 eV/atom
Cl4	0.00 eV/atom
Nb	0.00 eV/atom

Phonons

Minimum eigenvalue of Hessian [eV/Ų]

-6.77

Linear deformations

Stiffness tensor

Cij (N/m)	xx	yy	xy
xx	-181.04	240.29	0.97
yy	97.41	-32.31	0.35
xy	0.01	-0.01	-214.89

Stiffness tensor eigenvalues
Eigenvalue 0	-276.78 N/m
Eigenvalue 1	-214.89 N/m
Eigenvalue 2	63.43 N/m

Basic magnetic properties

Property	Value
Total magnetic moment [μB]	1.988
Magnetic anisotropy energy, xz [meV/unit cell]	-0.331
Magnetic anisotropy energy, yz [meV/unit cell]	-0.338

Heisenberg model	Value
Nearest neighbor exchange coupling [meV]	67.273
Single-ion anisotropy (out-of-plane) [meV]	0.000
Anisotropic exchange (out-of-plane) [meV]	0.288
Maximum value of Sz at magnetic sites	0.500
Number of nearest neighbors	3

Atom index	Atom type	Local spin magnetic moment (μB)	Local orbital magnetic moment (μB)
0	Nb	0.679	-0.029
1	Nb	0.679	-0.029
2	Cl	0.016	0.001
3	Cl	0.016	0.001
4	Cl	0.016	0.001
5	Cl	0.016	0.001
6	Cl	0.016	0.001
7	Cl	0.016	0.001

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)	-4.990

Fermi surface

Electronic properties

Bader charges

Atom No.	Chemical symbol	Charges [|e|]
0	Nb	1.76
1	Nb	1.76
2	Cl	-0.58
3	Cl	-0.59
4	Cl	-0.59
5	Cl	-0.58
6	Cl	-0.59
7	Cl	-0.59

Optical properties

Optical polarizability

Properties
Interband polarizability (x) [Å]	43.645
Interband polarizability (y) [Å]	43.645
Interband polarizability (z) [Å]	0.343
Plasma frequency (x) [eV Å0.5]	3.520
Plasma frequency (y) [eV Å0.5]	3.520

Miscellaneous

Miscellaneous details
Unique ID	2NbCl3-1
Number of atoms	8
Number of species	2
Formula	Nb2Cl6
Reduced formula	NbCl3
Stoichiometry	AB3
Unit cell area [Å2]	29.397
Original file-system folder	/home/niflheim2/cmr/C2DB-ASR/tree/AB3/NbCl3/Nb2Cl6-ca5dfc8256fa
Old uid	Nb2Cl6-ca5dfc8256fa
Space group (bulk in AA-stacking)	P-31m
Space group number (bulk in AA-stacking)	162
Point group	-3m
Inversion symmetry	Yes
Layer group number	71
Layer group	p-31m
2D Bravais type	Hexagonal (hp)
Thickness [Å]	3.024
Structure origin	original03-18
Band gap (PBE) [eV]	0.000
Direct band gap (PBE) [eV]	0.000
gap_dir_nosoc	0.000
Vacuum level [eV]	3.497

Miscellaneous details
Fermi level wrt. vacuum (PBE) [eV]	-4.990
minhessianeig	-6.770
Dynamically stable	No
Interband polarizability (x) [Å]	43.645
Interband polarizability (y) [Å]	43.645
Interband polarizability (z) [Å]	0.343
Plasma frequency (x) [eV Å0.5]	3.520
Plasma frequency (y) [eV Å0.5]	3.520
Energy [eV]	-41.126
Magnetic	Yes
Total magnetic moment [μB]	1.988
Spin axis	z
Magnetic anisotropy energy, xz [meV/unit cell]	-0.331
Magnetic anisotropy energy, yz [meV/unit cell]	-0.338
Nearest neighbor exchange coupling [meV]	67.273
Anisotropic exchange (out-of-plane) [meV]	0.288
Single-ion anisotropy (out-of-plane) [meV]	0.000
Maximum value of Sz at magnetic sites	0.500
Number of nearest neighbors	3
Energy above convex hull [eV/atom]	0.117
Heat of formation [eV/atom]	-1.220