material

GaSe
ID:

mp-1572
DOI:

10.17188/1191339

Warnings: [?]
  1. Large change in a lattice parameter during relaxation.
Tags: Gallium selenide - epsilon, 2H High pressure experimental phase Gallium selenide (1/1) - epsilon Gallium selenide (1/1)

Material Details

Final Magnetic Moment
-0.000 μB

Calculated total magnetic moment for the unit cell within the magnetic ordering provided (see below). Typically accurate to the second digit.
Magnetic Ordering
Non-magnetic
Formation Energy / Atom
-0.589 eV

Calculated formation energy from the elements normalized to per atom in the unit cell.

Energy Above Hull / Atom
< 0.001 eV

The energy of decomposition of this material into the set of most stable materials at this chemical composition, in eV/atom. Stability is tested against all potential chemical combinations that result in the material's composition. For example, a Co2O3 structure would be tested for decomposition against other Co2O3 structures, against Co and O2 mixtures, and against CoO and O2 mixtures.

Density
4.39 g/cm3

The calculated bulk crystalline density, typically underestimated due calculated cell volumes overestimated on average by 3% (+/- 6%)

Decomposes To
GaSe
Band Gap
1.241 eV

In general, band gaps computed with common exchange-correlation functionals such as the LDA and GGA are severely underestimated. Typically the disagreement is reported to be ~50% in the literature. Some internal testing by the Materials Project supports these statements; typically, we find that band gaps are underestimated by ~40%. We additionally find that several known insulators are predicted to be metallic.

Space Group

Hermann Mauguin
P6m2 [187]
Hall
P 6 2
Point Group
6m2
Crystal System
hexagonal

Band Structure

Density of States
Warning! Semi-local DFT tends to severely underestimate bandgaps. Please see the wiki for more info.

sign indicates spin ↑ ↓

X-Ray Diffraction

    Select radiation source:
  • Cu
  • Ag
  • Mo
  • Fe

Calculated powder diffraction pattern; note that peak spacings may be affected due to inaccuracies in calculated cell volume, which is typically overestimated on average by 3% (+/- 6%)

X-Ray Absorption Spectra

FEFF XANES

Select an element to display a spectrum averaged over all sites of that element in the structure.

Apply Gaussian smoothing:

0 eV
3 eV
FWHM: 0 eV

Download spectra for every symmetrically equivalent absorption site in the structure.

Download FEFF Input parameters.

Warning: These results are intended to be semi-quantitative in that corrections, such as edge shifts and Debye-Waller damping, have not been included.

Substrates

Reference for minimal coincident interface area (MCIA) and elastic energy:
substrate orientation:
substrate material substrate orientation film orientation elastic energy [meV] MCIA† [Å2]
CaCO3 (mp-3953) <0 0 1> <0 0 1> 0.000 88.4
Al2O3 (mp-1143) <0 0 1> <0 0 1> 0.000 240.0
GaSe (mp-1943) <0 0 1> <0 0 1> 0.000 12.6
GaSe (mp-1943) <1 1 1> <1 1 1> 0.001 118.4
GaSe (mp-1943) <1 0 1> <1 0 1> 0.001 69.1
GaSe (mp-1943) <1 1 0> <1 1 0> 0.001 117.8
GaSe (mp-1943) <1 0 0> <1 0 0> 0.001 68.0
C (mp-66) <1 1 1> <0 0 1> 0.001 88.4
LiTaO3 (mp-3666) <0 0 1> <0 0 1> 0.001 164.2
PbSe (mp-2201) <1 1 1> <0 0 1> 0.004 202.1
Mg (mp-153) <0 0 1> <0 0 1> 0.006 113.7
CdWO4 (mp-19387) <0 0 1> <1 0 0> 0.008 271.9
GaSb (mp-1156) <1 1 1> <0 0 1> 0.013 202.1
Te2Mo (mp-602) <1 0 0> <1 0 0> 0.015 271.9
LiNbO3 (mp-3731) <0 0 1> <0 0 1> 0.021 164.2
CdSe (mp-2691) <1 1 1> <0 0 1> 0.024 202.1
ZrO2 (mp-2858) <0 1 1> <1 0 0> 0.025 271.9
Cu (mp-30) <1 1 0> <1 0 0> 0.027 271.9
LaF3 (mp-905) <0 0 1> <0 0 1> 0.028 315.8
MoS2 (mp-1434) <0 0 1> <0 0 1> 0.028 113.7
WS2 (mp-224) <0 0 1> <0 0 1> 0.029 113.7
Ge (mp-32) <1 0 0> <0 0 1> 0.029 265.3
GaAs (mp-2534) <1 0 0> <0 0 1> 0.031 265.3
TiO2 (mp-390) <0 0 1> <0 0 1> 0.034 101.0
C (mp-66) <1 1 0> <1 0 0> 0.035 271.9
TePb (mp-19717) <1 0 0> <0 0 1> 0.035 303.1
C (mp-66) <1 0 0> <1 0 0> 0.039 271.9
AlN (mp-661) <1 0 1> <0 0 1> 0.039 303.1
ZnSe (mp-1190) <1 0 0> <0 0 1> 0.040 265.3
BN (mp-984) <0 0 1> <0 0 1> 0.041 37.9
CaCO3 (mp-3953) <1 0 1> <1 0 0> 0.041 271.9
Mg (mp-153) <1 0 1> <1 0 1> 0.041 276.6
ZnO (mp-2133) <1 1 1> <1 0 1> 0.042 276.6
LiF (mp-1138) <1 0 0> <0 0 1> 0.043 265.3
MgF2 (mp-1249) <0 0 1> <0 0 1> 0.044 240.0
TiO2 (mp-2657) <1 1 1> <0 0 1> 0.049 88.4
ZnO (mp-2133) <0 0 1> <0 0 1> 0.052 37.9
MoSe2 (mp-1634) <0 0 1> <0 0 1> 0.059 37.9
BN (mp-984) <1 0 0> <1 0 0> 0.060 136.0
WSe2 (mp-1821) <0 0 1> <0 0 1> 0.060 37.9
SiO2 (mp-6930) <0 0 1> <0 0 1> 0.069 88.4
WS2 (mp-224) <1 1 1> <0 0 1> 0.073 240.0
ZrO2 (mp-2858) <1 1 -1> <1 0 1> 0.079 138.3
Te2W (mp-22693) <0 1 0> <1 0 0> 0.080 271.9
ZnO (mp-2133) <1 0 0> <0 0 1> 0.080 138.9
BN (mp-984) <1 0 1> <0 0 1> 0.083 138.9
C (mp-48) <1 1 0> <0 0 1> 0.085 265.3
C (mp-48) <1 0 1> <0 0 1> 0.086 240.0
BaF2 (mp-1029) <1 1 1> <0 0 1> 0.095 202.1
LiF (mp-1138) <1 1 0> <0 0 1> 0.115 189.5
Up to 50 entries displayed.
†minimal coincident interface area.

Elasticity

Reference for tensor and properties:
Visualize with ELATE
Stiffness Tensor Cij (GPa)
78 18 2 0 -0 -0
18 78 2 0 -0 -0
2 2 5 0 0 -0
0 0 0 1 -0 0
-0 -0 0 -0 1 -0
-0 -0 -0 0 -0 30
Compliance Tensor Sij (10-12Pa-1)
13.6 -3.1 -4 0 0 0
-3.1 13.6 -4 0 0 0
-4 -4 197.7 0 0 0
0 0 0 1101.9 0 0
0 0 0 0 1101.9 0
0 0 0 0 0 33.4
Shear Modulus GV
16 GPa
Bulk Modulus KV
23 GPa
Shear Modulus GR
2 GPa
Bulk Modulus KR
5 GPa
Shear Modulus GVRH
9 GPa
Bulk Modulus KVRH
14 GPa
Elastic Anisotropy
38.56
Poisson's Ratio
0.24

Piezoelectricity

Reference for tensor and properties: Methodology
Piezoelectric Tensor eij (C/m2)
0.00000 -0.00000 0.00000 0.00000 0.00000 -0.09912
-0.09912 0.09912 0.00000 0.00000 0.00000 -0.00000
0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
Piezoelectric Modulus ‖eij‖max
0.14018 C/m2
Crystallographic Direction vmax
-0.00000
1.00000
0.00000

Dielectric Properties

Reference for tensor and properties: Methodology
Dielectric Tensor εij∞ (electronic contribution)
7.55 -0.00 0.00
-0.00 7.55 0.00
0.00 0.00 4.39
Dielectric Tensor εij (total)
10.70 -0.00 0.00
-0.00 10.70 0.00
0.00 0.00 4.58
Polycrystalline dielectric constant εpoly∞
(electronic contribution)
2.03
Polycrystalline dielectric constant εpoly
(total)
2.03
Refractive Index n
1.42
Potentially ferroelectric?
Unknown

Similar Structures beta feature

Explanation of dissimilarity measure: Documentation.
material dissimilarity Ehull # of elements
GaGeTe (mp-8211) 0.5437 0.006 3
Zn(InSe2)2 (mp-34169) 0.7003 0.001 3
Ga4GeS4 (mp-531297) 0.6609 0.019 3
In4SnS4 (mp-646878) 0.6467 0.000 3
In4GeS4 (mp-556528) 0.6836 0.000 3
LiFeSiO4 (mp-762837) 0.7351 0.042 4
LiVSiO4 (mp-767059) 0.7281 0.090 4
LiCoSiO4 (mp-763516) 0.7357 0.078 4
LiAlVO4 (mp-770103) 0.7228 0.084 4
LiCoSiO4 (mp-762904) 0.7251 0.077 4
GaSe (mp-568263) 0.0335 0.001 2
GaS (mp-556742) 0.1324 0.001 2
GaTe (mp-10009) 0.1145 0.004 2
GaSe (mp-1943) 0.0142 0.000 2
GaSe (mp-11342) 0.0104 0.000 2
Up to 5 similar elemental, binary, ternary, quaternary, etc. structures displayed (dissimilarity threshold 0.75). Ehull: energy above hull per atom [eV].

Calculation Summary

Elasticity

Methodology

Structure Optimization

Run Type
GGA
Energy Cutoff
520 eV
# of K-points
None
U Values
--
Pseudopotentials
VASP PAW: Ga_d Se
Final Energy/Atom
-3.8520 eV
Corrected Energy
-30.8157 eV
-30.8157 eV = -30.8157 eV (uncorrected energy)

Detailed input parameters and outputs for all calculations

Show JSON History Show BibTex Citation Download BibTex Citation
ICSD IDs
  • 73387
  • 71082
  • 660262
  • 635372
  • 601159
  • 635363
Submitted by
User remarks:
  • High pressure experimental phase
  • Gallium selenide (1/1) - epsilon

Displaying lattice parameters for primitive cell; note that calculated cell volumes are typically overestimated on average by 3% (+/- 6%). Note the primitive cell may appear less symmetric than the conventional cell representation (see "Structure Type" selector below the 3d structure)