| Structure info | |
|---|---|
| Layer group | p-4m2 |
| Layer group number | 59 |
| Structure origin | original03-18 |
| Stability | |
|---|---|
| Energy above convex hull [eV/atom] | 0.270 |
| Heat of formation [eV/atom] | -0.861 |
| Dynamically stable | Yes |
| Basic properties | |
|---|---|
| Magnetic | No |
| Band gap (PBE) [eV] | 0.878 |
| Band gap (HSE06) [eV] | 2.220 |
| Symmetries | |
|---|---|
| 2D Bravais type | Square (tp) |
| Layer group number | 59 |
| Layer group | p-4m2 |
| Space group number (bulk in AA-stacking) | 115 |
| Space group (bulk in AA-stacking) | P-4m2 |
| Point group | -42m |
| Inversion symmetry | No |
| Structure data | |
|---|---|
| Formula | TiSe2 |
| Stoichiometry | AB2 |
| Number of atoms | 3 |
| Unit cell area [Å2] | 14.659 |
| Thickness [Å] | 2.943 |
| TiSe2 (1TiSe2-3) | |
|---|---|
| Heat of formation [eV/atom] | -0.86 |
| Energy above convex hull [eV/atom] | 0.27 |
| 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 |
| Minimum eigenvalue of Hessian [eV/Ų] | -0.00 |
| DVB [eV] | xx | yy | xy |
| Γ | -3.23 | -3.23 | 0.00 |
| M | 2.04 | 2.04 | 0.00 |
| X | -5.26 | -0.62 | -0.00 |
| kVBM | -3.23 | -3.23 | 0.00 |
| xx | yy | xy | |
| Band gap [eV] | 2.01 | 2.01 | 0.60 |
| DCB [eV] | xx | yy | xy |
| Γ | 0.91 | 0.91 | 0.00 |
| M | -2.09 | -2.09 | 0.00 |
| X | -0.80 | -6.06 | 0.00 |
| kCBM | -1.22 | -1.22 | 0.60 |
| Cij (N/m) | xx | yy | xy |
| xx | 26.15 | 2.99 | 0.00 |
| yy | 2.99 | 26.15 | 0.00 |
| xy | 0.00 | 0.00 | 8.54 |
| Stiffness tensor eigenvalues | |
| Eigenvalue 0 | 8.54 N/m |
| Eigenvalue 1 | 23.17 N/m |
| Eigenvalue 2 | 29.14 N/m |
| cij [e/Å] | xx | yy | xy |
| x | 0.00 | 0.00 | -0.00 |
| y | 0.00 | 0.00 | -0.00 |
| z | 0.01 | -0.01 | 0.00 |
| cijclamped [e/Å] | xx | yy | xy |
| x | -0.00 | 0.00 | -0.00 |
| y | 0.00 | 0.00 | -0.00 |
| z | 0.03 | -0.03 | 0.00 |
| Key values [eV] | |
|---|---|
| Band gap (PBE) | 0.878 |
| Direct band gap (PBE) | 1.320 |
| Valence band maximum wrt. vacuum (PBE) | -5.906 |
| Conduction band minimum wrt. vacuum (PBE) | -5.028 |
| Key values [eV] | |
|---|---|
| Band gap (HSE06) | 2.220 |
| Direct band gap (HSE06) | 2.886 |
| Valence band maximum wrt. vacuum (HSE06) | -6.386 |
| Conduction band minimum wrt. vacuum (HSE06) | -4.166 |
| Property (VBM) | Value |
|---|---|
| Min eff. mass | 0.57 m0 |
| Max eff. mass | 57.25 m0 |
| DOS eff. mass | 5.62 m0 |
| Crystal coordinates | [0.000, 0.004] |
| Warping parameter | -0.003 |
| Barrier height | > 41.7 meV |
| Distance to barrier | > 0.0163 Å-1 |
| Property (CBM) | Value |
|---|---|
| Min eff. mass | 0.77 m0 |
| Max eff. mass | 1.59 m0 |
| DOS eff. mass | 1.10 m0 |
| Crystal coordinates | [0.362, 0.362] |
| Warping parameter | 0.001 |
| Barrier height | > 24.9 meV |
| Distance to barrier | > 0.0164 Å-1 |
| ZTiij | ux | uy | uz |
| Px | 4.75 | 0.00 | -0.00 |
| Py | -0.00 | 4.75 | 0.00 |
| Pz | 0.00 | -0.00 | 0.29 |
| ZSeij | ux | uy | uz |
| Px | -4.55 | -0.00 | -0.00 |
| Py | 0.00 | -0.20 | 0.00 |
| Pz | -0.00 | -0.00 | -0.15 |
| ZSeij | ux | uy | uz |
| Px | -0.20 | 0.00 | 0.00 |
| Py | 0.00 | -4.55 | -0.00 |
| Pz | 0.00 | 0.00 | -0.15 |
| Atom No. | Chemical symbol | Charges [|e|] |
|---|---|---|
| 0 | Ti | 1.57 |
| 1 | Se | -0.79 |
| 2 | Se | -0.79 |
| Properties | |
|---|---|
| Interband polarizability (x) [Å] | 3.681 |
| Interband polarizability (y) [Å] | 3.670 |
| Interband polarizability (z) [Å] | 0.349 |
| Plasma frequency (x) [eV Å0.5] | 0.000 |
| Plasma frequency (y) [eV Å0.5] | 0.000 |
| Static polarizability [Å] | |
|---|---|
| Phonons only (x) | 2.85 |
| Phonons only (y) | 2.85 |
| Phonons only (z) | 0.01 |
| Total (phonons + electrons) (x) | 6.53 |
| Total (phonons + electrons) (y) | 6.52 |
| Total (phonons + electrons) (z) | 0.35 |
| Element | Relations |
|---|---|
| xxz | xxz=xzx=-yyz=-yzy |
| Others | 0=xxx=yyy=xxy=xyy=xyz=xzy=xzz=yxx=yxy=yxz=yyx=xyx= yzx=yzz=zxy=zxz=zyx=zyz=zzx=zzy=zzz |
| zxx | zxx=-zyy |
| Element | Relations |
|---|---|
| xxz | xxz=xzx=-yyz=-yzy |
| Others | 0=xxx=yyy=xyx=xyy=xyz=xzy=xzz=yxx=yxy=yxz=yyx=xxy= yzx=yzz=zxy=zxz=zyx=zyz=zzx=zzy=zzz |
| zxx | zxx=-zyy |
| Mode | Frequency (1/cm) | Degeneracy |
|---|---|---|
| Mode 1 | 0. | 3 |
| Mode 2 | 56.8 | 2 |
| Mode 3 | 174.4 | 1 |
| Mode 4 | 271.9 | 2 |
| Mode 5 | 358.1 | 1 |
| Miscellaneous details | |
|---|---|
| Unique ID | 1TiSe2-3 |
| Number of atoms | 3 |
| Number of species | 2 |
| Formula | TiSe2 |
| Reduced formula | TiSe2 |
| Stoichiometry | AB2 |
| Unit cell area [Å2] | 14.659 |
| Original file-system folder | /home/niflheim2/cmr/C2DB-ASR/tree/AB2/TiSe2/TiSe2-0684166af1fd |
| Old uid | TiSe2-0684166af1fd |
| Space group (bulk in AA-stacking) | P-4m2 |
| Space group number (bulk in AA-stacking) | 115 |
| Point group | -42m |
| Inversion symmetry | No |
| Layer group number | 59 |
| Layer group | p-4m2 |
| 2D Bravais type | Square (tp) |
| Thickness [Å] | 2.943 |
| Structure origin | original03-18 |
| Band gap (PBE) [eV] | 0.878 |
| Direct band gap (PBE) [eV] | 1.320 |
| gap_dir_nosoc | 1.388 |
| Vacuum level [eV] | 2.746 |
| Fermi level wrt. vacuum (PBE) [eV] | -5.467 |
| Valence band maximum wrt. vacuum (PBE) [eV] | -5.906 |
| Conduction band minimum wrt. vacuum (PBE) [eV] | -5.028 |
| Miscellaneous details | |
|---|---|
| minhessianeig | -0.000 |
| Dynamically stable | Yes |
| Band gap (HSE06) [eV] | 2.220 |
| Direct band gap (HSE06) [eV] | 2.886 |
| Fermi level wrt. vacuum (HSE) [eV] | -5.276 |
| Valence band maximum wrt. vacuum (HSE06) [eV] | -6.386 |
| Conduction band minimum wrt. vacuum (HSE06) [eV] | -4.166 |
| Interband polarizability (x) [Å] | 3.681 |
| Interband polarizability (y) [Å] | 3.670 |
| Interband polarizability (z) [Å] | 0.349 |
| Static polarizability (phonons) (x) [Å] | 2.852 |
| Static polarizability (phonons + electrons) (x) [Å] | 6.533 |
| Static polarizability (phonons) (y) [Å] | 2.853 |
| Static polarizability (phonons + electrons) (y) [Å] | 6.522 |
| Static polarizability (phonons) (z) [Å] | 0.005 |
| Static polarizability (phonons + electrons) (z) [Å] | 0.354 |
| Plasma frequency (x) [eV Å0.5] | 0.000 |
| Plasma frequency (y) [eV Å0.5] | 0.000 |
| Energy [eV] | -16.239 |
| 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] | 0.270 |
| Heat of formation [eV/atom] | -0.861 |
