material

KNbO3

ID:

mp-4342

DOI:

10.17188/1208084


Tags: Potassium niobate - HT Potassium niobate

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
NM
Formation Energy / Atom
-2.854 eV

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

Energy Above Hull / Atom
0.002 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
4.37 g/cm3

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

Decomposes To
KNbO3
Band Gap
1.558 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
P4mm [99]
Hall
P 4 2
Point Group
4mm
Crystal System
tetragonal

Electronic Structure

Topological data for ICSD ID 9532 from Topological Materials Database
Topological Classification
trivial*
Subclassification
LCEBR
* trivial insulator or metal
Linear Combination of Elementary Band Representations

Band Structure and Density of States

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

Vibrational Properties

Reference for phonon calculations and visualization: Visualize with phononwebsite

Phonon dispersion

Density of States
Warning! These calculations were performed using a PBEsol exchange correlation functional in the framework of DFPT using the Abinit code. Please see the wiki for more info.

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]
KTaO3 (mp-3614) <1 0 0> <0 0 1> 0.001 16.2
NaCl (mp-22862) <1 0 0> <0 0 1> 0.003 32.5
Fe3O4 (mp-19306) <1 0 0> <0 0 1> 0.008 146.1
TiO2 (mp-390) <0 0 1> <0 0 1> 0.015 129.8
Al (mp-134) <1 0 0> <0 0 1> 0.022 16.2
BN (mp-984) <0 0 1> <1 0 0> 0.024 153.0
Ge(Bi3O5)4 (mp-23352) <1 0 0> <0 0 1> 0.024 211.0
CdS (mp-672) <1 1 0> <1 1 1> 0.026 348.0
MgO (mp-1265) <1 0 0> <1 1 0> 0.027 72.1
MgO (mp-1265) <1 1 0> <1 0 0> 0.029 51.0
Bi2Se3 (mp-541837) <1 0 1> <1 0 0> 0.030 254.9
C (mp-66) <1 1 0> <1 1 1> 0.030 145.0
NaCl (mp-22862) <1 1 1> <1 0 0> 0.032 170.0
Fe3O4 (mp-19306) <1 1 0> <1 0 0> 0.039 102.0
Fe3O4 (mp-19306) <1 1 1> <1 0 0> 0.039 254.9
Cu (mp-30) <1 0 0> <0 0 1> 0.045 64.9
InP (mp-20351) <1 1 1> <1 0 0> 0.046 305.9
KCl (mp-23193) <1 0 0> <0 0 1> 0.055 81.2
SiC (mp-11714) <0 0 1> <1 0 1> 0.055 164.5
BaTiO3 (mp-5986) <1 1 0> <1 1 0> 0.057 24.0
SiC (mp-7631) <0 0 1> <1 0 1> 0.063 164.5
BaTiO3 (mp-5986) <1 0 0> <1 0 0> 0.063 17.0
BaTiO3 (mp-5986) <1 1 1> <1 1 1> 0.070 29.0
YVO4 (mp-19133) <0 0 1> <0 0 1> 0.077 211.0
BN (mp-984) <1 1 0> <1 1 1> 0.077 203.0
GaTe (mp-542812) <0 0 1> <1 0 0> 0.081 153.0
BaTiO3 (mp-5986) <1 0 1> <1 0 1> 0.085 23.5
ZnSe (mp-1190) <1 1 1> <1 0 0> 0.087 170.0
Ga2O3 (mp-886) <1 1 0> <1 0 0> 0.088 288.9
MgO (mp-1265) <1 1 1> <1 0 0> 0.091 254.9
LiGaO2 (mp-5854) <1 1 0> <1 0 0> 0.091 288.9
GdScO3 (mp-5690) <1 0 0> <1 0 1> 0.095 47.0
GaTe (mp-542812) <1 0 0> <1 0 0> 0.099 136.0
Te2W (mp-22693) <0 1 0> <1 1 0> 0.102 216.3
SiO2 (mp-6930) <0 0 1> <1 0 1> 0.116 305.5
LiGaO2 (mp-5854) <0 1 1> <1 1 1> 0.118 87.0
NdGaO3 (mp-3196) <0 1 0> <1 0 1> 0.118 258.5
GdScO3 (mp-5690) <1 1 0> <0 0 1> 0.121 64.9
GaAs (mp-2534) <1 1 1> <1 0 0> 0.128 170.0
Ga2O3 (mp-886) <1 0 1> <0 0 1> 0.132 324.6
WSe2 (mp-1821) <1 1 1> <1 1 1> 0.138 87.0
TiO2 (mp-2657) <1 0 1> <1 0 1> 0.140 282.0
BaTiO3 (mp-5986) <0 0 1> <0 0 1> 0.150 16.2
YAlO3 (mp-3792) <0 1 0> <1 0 0> 0.152 153.0
CdWO4 (mp-19387) <1 0 1> <1 0 1> 0.156 352.5
Al2O3 (mp-1143) <0 0 1> <1 0 0> 0.162 102.0
ZrO2 (mp-2858) <0 1 1> <1 1 0> 0.170 192.3
Bi2Se3 (mp-541837) <1 0 0> <1 0 0> 0.172 254.9
CdWO4 (mp-19387) <0 0 1> <0 0 1> 0.173 243.5
YAlO3 (mp-3792) <1 1 0> <0 0 1> 0.183 275.9
Up to 50 entries displayed.
minimal coincident interface area.

Elasticity

Reference for tensor and properties:
Stiffness Tensor Cij (GPa)
321 83 68 0 0 0
83 321 68 0 0 0
68 68 82 0 0 0
0 0 0 64 0 0
0 0 0 0 64 0
0 0 0 0 0 86
Compliance Tensor Sij (10-12Pa-1)
3.8 -0.4 -2.8 0 0 0
-0.4 3.8 -2.8 0 0 0
-2.8 -2.8 16.9 0 0 0
0 0 0 15.6 0 0
0 0 0 0 15.6 0
0 0 0 0 0 11.6
Shear Modulus GV
77 GPa
Bulk Modulus KV
129 GPa
Shear Modulus GR
60 GPa
Bulk Modulus KR
80 GPa
Shear Modulus GVRH
68 GPa
Bulk Modulus KVRH
105 GPa
Elastic Anisotropy
1.99
Poisson's Ratio
0.23

Piezoelectricity

Reference for tensor and properties: Methodology
Piezoelectric Tensor eij (C/m2)
0.00000 0.00000 0.00000 0.00000 0.37878 0.00000
0.00000 0.00000 0.00000 0.37878 0.00000 0.00000
-0.11636 -0.11636 3.25783 0.00000 0.00000 0.00000
Piezoelectric Modulus ‖eijmax
3.26198 C/m2
Crystallographic Direction vmax
0.00000
0.00000
1.00000

Dielectric Properties

Reference for tensor and properties: Methodology
Dielectric Tensor εij (electronic contribution)
6.21 0.00 0.00
0.00 6.21 0.00
0.00 0.00 4.59
Dielectric Tensor εij (total)
12.02 0.00 0.00
0.00 12.02 0.00
0.00 0.00 12.98
Polycrystalline dielectric constant εpoly
(electronic contribution)
5.67
Polycrystalline dielectric constant εpoly
(total)
12.34
Refractive Index n
2.38
Potentially ferroelectric?
Unknown

Similar Structures beta feature

Explanation of dissimilarity measure: Documentation.
material dissimilarity Ehull # of elements
TlGeCl3 (mp-998744) 0.6193 0.033 3
CsGeI3 (mp-642690) 0.5470 0.009 3
BaTiO3 (mp-5777) 0.4839 0.000 3
KNbO3 (mp-5246) 0.5152 0.000 3
BaTiO3 (mp-5986) 0.1294 0.003 3
Ba3Nb2CoO9 (mp-561599) 0.6876 0.002 4
SrTaNO2 (mp-754505) 0.6826 0.013 4
K2NaNb(OF2)2 (mp-684816) 0.7250 0.089 5
KNaMo(OF2)2 (mp-975958) 0.5786 0.032 5
K2NaMo(OF)3 (mp-706271) 0.6137 0.022 5
Cs2ZrTlOF5 (mp-42227) 0.7224 0.017 5
K2NaTiOF5 (mp-42190) 0.7075 0.000 5
Up to 5 similar elemental, binary, ternary, quaternary, etc. structures displayed (dissimilarity threshold 0.75). Ehull: energy above hull per atom [eV].

Synthesis Descriptions

KSr2Nb5O15 (KSN) ceramics were prepared by reactive sintering of SrNb2O6 (SN) and KNbO3 (KN) powders. SN or KN was first synthesized by solid-state reaction of SrCO3 (Alfa) or K2CO3 (Merck) and Nb2O5 [...]
Because of the presence of OH and H2O in the KN unit cell, tetragonal KNbO3 (KN) nanowires were formed when the synthesis was carried out at 120C for 48h. However, when the fabrication was conduct [...]
chef hat mixing beaker

Explore more synthesis descriptions for materials of composition KNbO3.

Text computed by synthesisproject.org.

Calculation Summary

Elasticity

Methodology

Structure Optimization

Run Type
GGA
Energy Cutoff
520 eV
# of K-points
None
U Values
--
Pseudopotentials
VASP PAW: K_sv Nb_pv O
Final Energy/Atom
-7.6531 eV
Corrected Energy
-40.3265 eV
Uncorrected energy = -38.2655 eV Composition-based energy adjustment (-0.687 eV/atom x 3.0 atoms) = -2.0610 eV Corrected energy = -40.3265 eV

Detailed input parameters and outputs for all calculations


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ICSD IDs
  • 9532
  • 9535
  • 190921
Submitted by
User remarks:
  • Potassium niobate - HT

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)