Fe3Co2Ni(PO4)6

High-Entropy Materials HEA

MP-ID: mp-758190 · Space group: R3 (#146)

Materials Project API

Basic Information

Formula

Fe3Co2Ni(PO4)6

MP-ID

mp-758190

Elements

Sites

Density

3.4781

g/cm³

Volume

436.33

Å³

Cell a

8.4015

Cell b

8.4015

Cell c

8.4015

α Angle

61.81

β Angle

61.81

γ Angle

61.81

Space Group

Point Group

Crystal System

Trigonal

Bravais Lattice

Stability

Packing Fraction

X-ray Diffraction

Diffraction Pattern

Target / Radiation

X-axis: 2θ (°); Y-axis: relative intensity; Cu Kα ; λ=1.5418 Å

Diffraction Peaks (Top 24)

2θ	d (Å)	I	hkl
14.72	6.0177	4.0	(1,1,0)
20.58	4.3151	96.7	(1,0,-1)
21.17	4.1977	10.1	(2,1,1)
24.47	3.6380	100.0	(2,1,0)
25.40	3.5067	17.0	(2,0,0)
29.69	3.0089	7.0	(2,2,0)
31.99	2.7979	15.0	(2,0,-1)
32.91	2.7214	5.1	(2,1,-1)
33.67	2.6620	24.7	(3,2,1)
33.67	2.6620	49.4	(3,1,2)
36.05	2.4913	45.9	(2,-1,-1)
36.40	2.4681	5.1	(3,1,0)
37.44	2.4021	1.1	(3,3,2)
38.84	2.3186	1.7	(3,0,2)
41.87	2.1576	2.3	(2,0,-2)
43.10	2.0988	11.0	(4,2,2)
44.05	2.0555	2.1	(3,1,-1)
44.80	2.0232	1.0	(4,2,1)
45.20	2.0059	7.0	(3,3,0)
45.38	1.9985	3.8	(4,3,2)
48.22	1.8874	11.0	(4,3,1)
48.22	1.8874	22.0	(4,1,3)
49.37	1.8461	5.6	(4,1,0)
50.15	1.8190	29.5	(4,2,0)

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Energy Properties

Formation Energy/atom

-2.11204

eV/atom

Energy/atom

-7.57596

eV/atom

Energy above Hull

0.1111

eV/atom

Uncorrected Energy

-6.7684

eV/atom

Volume/atom

12.12

Å³

c/a Ratio

1.0000

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

20.5053

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.047000

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

O · 0.667

Element Family

Metalloid-Nonmetal

Solute Fraction

0.333

Interstitial Fraction

0.167

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.0361

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

8.6144

J/mol·K

Ω Parameter

1.4119

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

34.768%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.6739

smaller = more stable mixing

VEC

4.944

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-2.358

kJ/mol; negative = exothermic mixing

Entropy Norm

0.6438

SS Former

Phase Tendency

Related Tasks

Related computation task IDs (2)

aaabywjt aaadzjfn

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-758190

Reference Citation

The crystal structure and related material properties of Fe3Co2Ni(PO4)6 were obtained from the Materials Project database (MP-ID: mp-758190, 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_Fe3Co2Ni(PO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.40153030
_cell_length_b   8.40153030
_cell_length_c   8.40152992
_cell_angle_alpha   61.80936037
_cell_angle_beta   61.80936037
_cell_angle_gamma   61.80935646
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Fe3Co2Ni(PO4)6
_chemical_formula_sum   'Fe3 Co2 Ni1 P6 O24'
_cell_volume   436.32827289
_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
  Fe  Fe0  1  0.64521800  0.64521800  0.64521800  1.0
  Fe  Fe1  1  0.85558800  0.85558800  0.85558800  1.0
  Fe  Fe2  1  0.35560000  0.35560000  0.35560000  1.0
  Co  Co3  1  0.00067000  0.00067000  0.00067000  1.0
  Co  Co4  1  0.50053600  0.50053600  0.50053600  1.0
  Ni  Ni5  1  0.14251600  0.14251600  0.14251600  1.0
  P  P6  1  0.95367100  0.24880400  0.54795100  1.0
  P  P7  1  0.54795100  0.95367100  0.24880400  1.0
  P  P8  1  0.24880400  0.54795100  0.95367100  1.0
  P  P9  1  0.75204300  0.44980700  0.04692300  1.0
  P  P10  1  0.44980700  0.04692300  0.75204300  1.0
  P  P11  1  0.04692300  0.75204300  0.44980700  1.0
  O  O12  1  0.50505100  0.10842300  0.32323700  1.0
  O  O13  1  0.32323700  0.50505100  0.10842300  1.0
  O  O14  1  0.10842300  0.32323700  0.50505100  1.0
  O  O15  1  0.94034000  0.09306200  0.75308700  1.0
  O  O16  1  0.98916200  0.17857900  0.39487300  1.0
  O  O17  1  0.74874600  0.40356100  0.56615300  1.0
  O  O18  1  0.75308700  0.94034000  0.09306200  1.0
  O  O19  1  0.56615300  0.74874600  0.40356100  1.0
  O  O20  1  0.82634900  0.60528600  0.00316100  1.0
  O  O21  1  0.40356100  0.56615300  0.74874600  1.0
  O  O22  1  0.90552900  0.24641700  0.06043900  1.0
  O  O23  1  0.60528600  0.00316100  0.82634900  1.0
  O  O24  1  0.39487300  0.98916200  0.17857900  1.0
  O  O25  1  0.09306200  0.75308700  0.94034000  1.0
  O  O26  1  0.59682700  0.43841200  0.25030100  1.0
  O  O27  1  0.17857900  0.39487300  0.98916200  1.0
  O  O28  1  0.43841200  0.25030100  0.59682700  1.0
  O  O29  1  0.24641700  0.06043900  0.90552900  1.0
  O  O30  1  0.25030100  0.59682700  0.43841200  1.0
  O  O31  1  0.00316100  0.82634900  0.60528600  1.0
  O  O32  1  0.06043900  0.90552900  0.24641700  1.0
  O  O33  1  0.89294500  0.67543800  0.49529300  1.0
  O  O34  1  0.67543800  0.49529300  0.89294500  1.0
  O  O35  1  0.49529300  0.89294500  0.67543800  1.0

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