KMg6CoO8
High-Entropy Materials HEAMP-ID: mp-1032180 · Space group: P4/mmm (#123)
Basic Information
Formula
KMg6CoO8
MP-ID
mp-1032180
Elements
4
Sites
16
Density
3.6467
g/cm³
Volume
169.32
ų
Cell a
8.8687
Å
Cell b
4.3695
Å
Cell c
4.3695
Å
α Angle
90.00
°
β Angle
90.00
°
γ Angle
90.00
°
Space Group
P4/mmm
Point Group
4/mmm
Crystal System
Tetragonal
Bravais Lattice
tP
Stability
No
Packing Fraction
-
X-ray Diffraction
Diffraction Pattern
X-axis: 2θ (°); Y-axis: relative intensity; Cu Kα ; λ=1.5418 Å
Diffraction Peaks (Top 24)
| 2θ | d (Å) | I | hkl |
|---|---|---|---|
| 9.97 | 8.8687 | 17.3 | (1,0,0) |
| 20.02 | 4.4343 | 6.9 | (2,0,0) |
| 20.32 | 4.3695 | 1.8 | (0,1,0) |
| 22.69 | 3.9196 | 4.9 | (1,1,0) |
| 28.68 | 3.1124 | 1.4 | (2,1,0) |
| 28.90 | 3.0897 | 5.0 | (0,1,1) |
| 30.23 | 2.9562 | 5.8 | (3,0,0) |
| 30.64 | 2.9177 | 8.9 | (1,1,1) |
| 35.41 | 2.5350 | 33.1 | (2,1,1) |
| 40.69 | 2.2172 | 50.1 | (4,0,0) |
| 41.33 | 2.1848 | 100.0 | (0,2,0) |
| 42.31 | 2.1360 | 2.5 | (3,1,1) |
| 42.62 | 2.1213 | 1.9 | (1,2,0) |
| 46.33 | 1.9598 | 2.6 | (2,2,0) |
| 47.65 | 1.9083 | 1.4 | (1,2,1) |
| 50.68 | 1.8014 | 1.5 | (4,1,1) |
| 52.05 | 1.7570 | 4.2 | (3,2,0) |
| 55.95 | 1.6435 | 1.1 | (5,1,0) |
| 59.39 | 1.5562 | 55.9 | (4,2,0) |
| 59.87 | 1.5449 | 28.5 | (0,2,2) |
| 60.15 | 1.5383 | 1.5 | (5,1,1) |
| 68.53 | 1.3692 | 1.6 | (3,2,2) |
| 68.76 | 1.3653 | 1.3 | (1,3,1) |
| 70.64 | 1.3334 | 6.1 | (6,1,1) |
Energy Properties
Formation Energy/atom
-2.33220
eV/atom
Energy/atom
-5.93416
eV/atom
Energy above Hull
0.3226
eV/atom
Uncorrected Energy
-5.4883
eV/atom
Volume/atom
10.58
ų
c/a Ratio
0.4927
Electronic Properties
Metallic
Metal
Band Gap
0
eV
Direct Gap
No
CBM
N/A
eV
Magnetic Properties
Magnetic
Yes
Total Mag. Moment
4.0002
μB
Mag. Ordering
FM
Mag. Sites
3
Magnetization/Volume
0.023620
μB/ų
Elastic Properties
Elastic data not available
Feature Analysis
Composition Overview
Element Composition (atomic fraction)
Composition Info
Major / Matrix Element
O · 0.500
Element Family
Metalloid-Nonmetal
Solute Fraction
0.500
Interstitial Fraction
0.000
High-Entropy Alloy Features
Composite Radar (normalized)
Element-Class Share
Mix Entropy ΔS/R
1.0610
HEA criterion (>1.0 = high entropy)
Mix Entropy ΔS
8.8208
J/mol·K
Ω Parameter
1.5898
Ω > 1.1 favors solid solution
Atomic Size Mismatch δr
48.729%
δr < 6.6% favors single-phase solid solution
Electronegativity Diff Δχ
1.0765
smaller = more stable mixing
VEC
3.375
valence electron concentration, affects phase stability
Mix Enthalpy ΔH_mix
-2.802
kJ/mol; negative = exothermic mixing
Entropy Norm
0.7653
SS Former
0
Phase Tendency
IM
Related Tasks
Citation & References
Materials Project Page
https://materialsproject.org/materials/mp-1032180
Reference Citation
The crystal structure and related material properties of KMg6CoO8 were obtained from the Materials Project database (MP-ID: mp-1032180, database version v2026.04.13).
Literature Citation
Horton, M.K., Huck, P., Yang, R.X. et al. Accelerated data-driven materials science with the Materials Project. Nat. Mater. 24, 1522–1532 (2025). https://doi.org/10.1038/s41563-025-02272-0
3D Crystal Structure Rendering
Loading 3D structure…
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Raw CIF Data
# generated using pymatgen
data_KMg6CoO8
_symmetry_space_group_name_H-M 'P 1'
_cell_length_a 8.86864569
_cell_length_b 4.36950054
_cell_length_c 4.36950054
_cell_angle_alpha 90.00000000
_cell_angle_beta 90.00000000
_cell_angle_gamma 90.00000000
_symmetry_Int_Tables_number 1
_chemical_formula_structural KMg6CoO8
_chemical_formula_sum 'K1 Mg6 Co1 O8'
_cell_volume 169.32492796
_cell_formula_units_Z 1
loop_
_symmetry_equiv_pos_site_id
_symmetry_equiv_pos_as_xyz
1 'x, y, z'
loop_
_atom_site_type_symbol
_atom_site_label
_atom_site_symmetry_multiplicity
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
K K0 1 0.00000000 0.50000000 0.50000000 1.0
Mg Mg1 1 0.50000000 0.00000000 0.00000000 1.0
Mg Mg2 1 0.50000000 0.50000000 0.50000000 1.0
Mg Mg3 1 0.25946374 0.00000000 0.50000000 1.0
Mg Mg4 1 0.74053626 0.00000000 0.50000000 1.0
Mg Mg5 1 0.25946374 0.50000000 0.00000000 1.0
Mg Mg6 1 0.74053626 0.50000000 0.00000000 1.0
Co Co7 1 0.00000000 0.00000000 0.00000000 1.0
O O8 1 0.24760227 0.00000000 0.00000000 1.0
O O9 1 0.75239773 0.00000000 0.00000000 1.0
O O10 1 0.27495069 0.50000000 0.50000000 1.0
O O11 1 0.72504931 0.50000000 0.50000000 1.0
O O12 1 0.00000000 0.00000000 0.50000000 1.0
O O13 1 0.50000000 0.00000000 0.50000000 1.0
O O14 1 0.00000000 0.50000000 0.00000000 1.0
O O15 1 0.50000000 0.50000000 0.00000000 1.0
