material

K2MgF4

ID:

mp-31212

DOI:

10.17188/1205509


Tags: Dipotassium magnesium fluoride

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
Unknown
Formation Energy / Atom
-3.400 eV

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

Energy Above Hull / Atom
0.000 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
2.73 g/cm3

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

Decomposes To
Stable
Band Gap
6.406 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
I4/mmm [139]
Hall
-I 4 2
Point Group
4/mmm
Crystal System
tetragonal

Band Structure

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

sign indicates spin ↑ ↓

  • 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]
TiO2 (mp-390) <0 0 1> <0 0 1> 0.000 130.3
Al (mp-134) <1 0 0> <0 0 1> 0.001 16.3
Ge(Bi3O5)4 (mp-23352) <1 0 0> <0 0 1> 0.001 211.7
KTaO3 (mp-3614) <1 0 0> <0 0 1> 0.001 16.3
Cu (mp-30) <1 0 0> <0 0 1> 0.004 65.1
KCl (mp-23193) <1 0 0> <0 0 1> 0.006 81.4
TePb (mp-19717) <1 1 1> <1 0 1> 0.007 225.1
NaCl (mp-22862) <1 0 0> <0 0 1> 0.007 32.6
SiC (mp-7631) <0 0 1> <1 0 1> 0.008 225.1
Te2W (mp-22693) <0 1 1> <1 1 1> 0.009 233.7
SiC (mp-11714) <0 0 1> <1 0 1> 0.010 225.1
AlN (mp-661) <1 0 1> <0 0 1> 0.010 195.4
Fe3O4 (mp-19306) <1 0 0> <0 0 1> 0.010 146.5
ZnO (mp-2133) <0 0 1> <0 0 1> 0.011 179.1
Ni (mp-23) <1 1 0> <0 0 1> 0.017 244.2
Ni (mp-23) <1 1 1> <0 0 1> 0.018 341.9
ZnO (mp-2133) <1 1 0> <1 1 0> 0.020 152.4
DyScO3 (mp-31120) <1 0 0> <0 0 1> 0.022 228.0
LaAlO3 (mp-2920) <1 0 1> <1 0 1> 0.025 225.1
AlN (mp-661) <1 0 0> <1 0 1> 0.027 281.4
Bi2Te3 (mp-34202) <0 0 1> <1 0 1> 0.028 225.1
MgO (mp-1265) <1 0 0> <0 0 1> 0.033 146.5
BaTiO3 (mp-5986) <1 0 0> <1 0 1> 0.034 168.8
YAlO3 (mp-3792) <1 1 0> <0 0 1> 0.038 276.8
GaN (mp-804) <1 0 1> <1 0 0> 0.043 269.4
ZnSe (mp-1190) <1 0 0> <0 0 1> 0.043 32.6
YVO4 (mp-19133) <0 0 1> <0 0 1> 0.044 211.7
CdWO4 (mp-19387) <0 0 1> <0 0 1> 0.045 244.2
TbScO3 (mp-31119) <1 0 0> <0 0 1> 0.046 228.0
YAlO3 (mp-3792) <0 1 0> <0 0 1> 0.047 309.4
Ga2O3 (mp-886) <1 0 1> <0 0 1> 0.052 325.7
LaAlO3 (mp-2920) <0 0 1> <1 0 1> 0.053 225.1
LaAlO3 (mp-2920) <1 0 0> <1 0 0> 0.054 215.5
Al (mp-134) <1 1 1> <1 1 0> 0.054 228.6
CdTe (mp-406) <1 1 1> <1 0 1> 0.056 225.1
WSe2 (mp-1821) <1 1 0> <0 0 1> 0.057 260.5
C (mp-48) <1 0 0> <0 0 1> 0.059 309.4
GdScO3 (mp-5690) <1 1 0> <0 0 1> 0.061 65.1
GaAs (mp-2534) <1 0 0> <0 0 1> 0.064 32.6
InSb (mp-20012) <1 1 1> <1 0 1> 0.066 225.1
MoS2 (mp-1434) <0 0 1> <0 0 1> 0.069 325.7
Mg (mp-153) <0 0 1> <0 0 1> 0.069 325.7
WS2 (mp-224) <0 0 1> <0 0 1> 0.069 325.7
YAlO3 (mp-3792) <1 1 1> <0 0 1> 0.072 309.4
PbS (mp-21276) <1 0 0> <0 0 1> 0.072 146.5
BaTiO3 (mp-5986) <0 0 1> <0 0 1> 0.073 16.3
LiNbO3 (mp-3731) <0 0 1> <1 1 1> 0.078 311.6
MgAl2O4 (mp-3536) <1 1 0> <1 0 1> 0.082 281.4
KTaO3 (mp-3614) <1 1 1> <1 1 0> 0.082 228.6
ZrO2 (mp-2858) <1 1 -1> <1 0 0> 0.086 323.2
Up to 50 entries displayed.
minimal coincident interface area.

Elasticity

Reference for tensor and properties:
Stiffness Tensor Cij (GPa)
88 24 28 -0 0 0
24 88 28 0 0 0
28 28 84 -0 0 0
-0 0 -0 19 0 0
0 0 0 0 19 0
0 0 0 0 0 31
Compliance Tensor Sij (10-12Pa-1)
13.1 -2.4 -3.6 0 0 0
-2.4 13.1 -3.6 0 0 0
-3.6 -3.6 14.4 0 0 0
0 0 0 51.7 0 0
0 0 0 0 51.7 0
0 0 0 0 0 32.4
Shear Modulus GV
26 GPa
Bulk Modulus KV
47 GPa
Shear Modulus GR
25 GPa
Bulk Modulus KR
47 GPa
Shear Modulus GVRH
25 GPa
Bulk Modulus KVRH
47 GPa
Elastic Anisotropy
0.26
Poisson's Ratio
0.27

Dielectric Properties

Reference for tensor and properties: Methodology
Dielectric Tensor εij (electronic contribution)
2.00 -0.00 -0.00
-0.00 2.00 -0.00
-0.00 -0.00 1.99
Dielectric Tensor εij (total)
7.28 -0.15 -0.47
-0.15 7.25 -0.51
-0.47 -0.51 5.80
Polycrystalline dielectric constant εpoly
(electronic contribution)
1.99
Polycrystalline dielectric constant εpoly
(total)
6.78
Refractive Index n
1.41
Potentially ferroelectric?
True

Calculation Summary

Elasticity

Methodology

Structure Optimization

Run Type
GGA
Energy Cutoff
520 eV
# of K-points
64
U Values
--
Pseudopotentials
VASP PAW: F Mg_pv K_sv
Final Energy/Atom
-4.7532 eV
Corrected Energy
-33.2724 eV
-33.2724 eV = -33.2724 eV (uncorrected energy)

Detailed input parameters and outputs for all calculations


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ICSD IDs
  • 33519

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)