Overview: AgI₂

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

Stability
Energy above convex hull [eV/atom]	0.205
Heat of formation [eV/atom]	0.025
Dynamically stable	No

Basic properties
Magnetic	No
Band gap (PBE) [eV]	0.000

Repeat: 1234   Download: XYZ CIF JSON

Axis	x [Å]	y [Å]	z [Å]	Periodic
1	4.001	0.000	0.000	Yes
2	-2.000	3.465	0.000	Yes
3	0.000	0.000	18.860	No

Lengths [Å]	4.001	4.001	18.860
Angles [°]	90.000	90.000	120.000

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	AgI2
Stoichiometry	AB2
Number of atoms	3
Unit cell area [Å2]	13.862
Thickness [Å]	3.860

Stability

Convex hull

AgI2 (1AgI2-3)
Heat of formation [eV/atom]	0.03
Energy above convex hull [eV/atom]	0.20

Monolayers from C2DB
Ag2I2 (2AgI-1)	-0.26 eV/atom
Ag2I2 (2AgI-2)	-0.25 eV/atom
Ag6I6 (6AgI-1)	-0.24 eV/atom
Ag5I5 (5AgI-1)	-0.24 eV/atom
Ag6I6 (6AgI-2)	-0.23 eV/atom
Ag2I2 (2AgI-3)	-0.22 eV/atom
Ag6I6 (6AgI-3)	-0.22 eV/atom
Ag6I6 (6AgI-4)	-0.21 eV/atom
Ag3I3 (3AgI-1)	-0.21 eV/atom
Ag3I3 (3AgI-2)	-0.21 eV/atom
AgI (1AgI-1)	-0.20 eV/atom
Ag2I2 (2AgI-4)	-0.19 eV/atom
Ag6I8 (2Ag3I4-1)	-0.19 eV/atom
I12Ag15 (3I4Ag5-1)	-0.17 eV/atom
Ag6I12 (6AgI2-1)	-0.16 eV/atom
Ag3I5 (1Ag3I5-1)	-0.14 eV/atom
Ag2I6 (2AgI3-1)	-0.13 eV/atom
Ag4I8 (4AgI2-1)	-0.12 eV/atom
Ag2I4 (2AgI2-1)	-0.12 eV/atom
Ag2I6 (2AgI3-2)	-0.11 eV/atom
Ag4I8 (4AgI2-2)	-0.10 eV/atom
Ag4I12 (4AgI3-1)	-0.09 eV/atom
Ag2I4 (2AgI2-2)	-0.08 eV/atom
AgI3 (1AgI3-1)	-0.07 eV/atom
AgI2 (1AgI2-1)	-0.06 eV/atom
AgI2 (1AgI2-2)	-0.06 eV/atom
AgI2, (1AgI2-3)	0.03 eV/atom
Ag2I6 (2AgI3-3)	0.07 eV/atom
Ag2I6 (2AgI3-4)	0.07 eV/atom
Ag2 (2Ag-1)	0.31 eV/atom

Bulk crystals from OQMD123
AgI	-0.27 eV/atom
Ag4	0.00 eV/atom
I4	0.00 eV/atom

Phonons

Minimum eigenvalue of Hessian [eV/Ų]

-0.97

Linear deformations

Stiffness tensor

Cij (N/m)	xx	yy	xy
xx	7.90	13.40	-0.03
yy	13.71	7.43	-0.03
xy	0.00	0.00	-5.83

Stiffness tensor eigenvalues
Eigenvalue 0	-5.89 N/m
Eigenvalue 1	-5.83 N/m
Eigenvalue 2	21.22 N/m

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)	-5.916

Fermi surface

Electronic properties

Bader charges

Atom No.	Chemical symbol	Charges [|e|]
0	Ag	0.35
1	I	-0.18
2	I	-0.18

Optical properties

Optical polarizability

Properties
Interband polarizability (x) [Å]	29.994
Interband polarizability (y) [Å]	29.994
Interband polarizability (z) [Å]	0.491
Plasma frequency (x) [eV Å0.5]	5.104
Plasma frequency (y) [eV Å0.5]	5.104

Miscellaneous

Miscellaneous details
Unique ID	1AgI2-3
Number of atoms	3
Number of species	2
Formula	AgI2
Reduced formula	AgI2
Stoichiometry	AB2
Unit cell area [Å2]	13.862
Original file-system folder	/home/niflheim2/cmr/C2DB-ASR/tree/AB2/AgI2/AgI2-ec7730622ee1
Old uid	AgI2-ec7730622ee1
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]	3.860
Structure origin	original03-18
Band gap (PBE) [eV]	0.000

Miscellaneous details
Direct band gap (PBE) [eV]	0.000
gap_dir_nosoc	0.000
Vacuum level [eV]	3.603
Fermi level wrt. vacuum (PBE) [eV]	-5.916
minhessianeig	-0.970
Dynamically stable	No
Interband polarizability (x) [Å]	29.994
Interband polarizability (y) [Å]	29.994
Interband polarizability (z) [Å]	0.491
Plasma frequency (x) [eV Å0.5]	5.104
Plasma frequency (y) [eV Å0.5]	5.104
Energy [eV]	-5.720
Magnetic	No
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]	0.205
Heat of formation [eV/atom]	0.025