Li2Fe(CoO3)2

High-Entropy Materials HEA

MP-ID: mp-757742 · Space group: Cmce (#64)

Materials Project API

Basic Information

Formula

Li2Fe(CoO3)2

MP-ID

mp-757742

Elements

Sites

Density

4.4636

g/cm³

Volume

211.00

Å³

Cell a

4.9599

Cell b

9.9910

Cell c

4.9273

α Angle

90.01

β Angle

59.79

γ Angle

90.00

Space Group

Cmce

Point Group

mmm

Crystal System

Orthorhombic

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
17.76	4.9955	100.0	(0,2,0)
35.96	2.4978	4.9	(0,4,0)
36.22	2.4799	7.3	(2,0,1)
37.60	2.3923	7.1	(1,1,-1)
37.60	2.3921	7.1	(1,-1,2)
37.60	2.3920	7.1	(1,-1,-1)
37.61	2.3918	7.1	(1,1,2)
40.62	2.2213	7.3	(2,-2,1)
40.62	2.2213	7.3	(2,2,1)
40.83	2.2099	1.7	(1,2,-1)
40.84	2.2097	1.7	(1,-2,2)
40.84	2.2095	1.7	(1,-2,-1)
40.85	2.2093	1.7	(1,2,2)
45.61	1.9890	1.4	(2,-3,1)
45.61	1.9890	1.4	(2,3,1)
45.81	1.9809	7.4	(1,3,-1)
45.81	1.9808	7.4	(1,-3,2)
45.82	1.9805	7.4	(1,-3,-1)
45.82	1.9803	7.4	(1,3,2)
51.96	1.7598	6.4	(2,-4,1)
51.96	1.7598	6.4	(2,4,1)
55.16	1.6652	1.1	(0,6,0)
59.56	1.5521	4.1	(1,5,-1)
59.56	1.5521	4.1	(1,-5,2)

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Energy Properties

Formation Energy/atom

-1.58884

eV/atom

Energy/atom

-6.70179

eV/atom

Energy above Hull

0.0805

eV/atom

Uncorrected Energy

-5.8242

eV/atom

Volume/atom

9.59

Å³

c/a Ratio

0.9934

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

0.0000

μB

Mag. Ordering

AFM

Mag. Sites

Magnetization/Volume

0.000000

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

O · 0.545

Element Family

Metalloid-Nonmetal

Solute Fraction

0.455

Interstitial Fraction

0.000

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.1685

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

9.7151

J/mol·K

Ω Parameter

0.9520

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

41.097%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

1.0044

smaller = more stable mixing

VEC

4.727

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-6.107

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8429

SS Former

Phase Tendency

Related Tasks

Related computation task IDs (2)

aaabywee aaaeisff

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-757742

Reference Citation

The crystal structure and related material properties of Li2Fe(CoO3)2 were obtained from the Materials Project database (MP-ID: mp-757742, 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

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Raw CIF Data

# generated using pymatgen
data_Li2Fe(CoO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.95985468
_cell_length_b   9.99100710
_cell_length_c   4.92725330
_cell_angle_alpha   90.01401928
_cell_angle_beta   59.78824537
_cell_angle_gamma   90.00015263
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Li2Fe(CoO3)2
_chemical_formula_sum   'Li4 Fe2 Co4 O12'
_cell_volume   211.00030084
_cell_formula_units_Z   2
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
  Li  Li0  1  0.16352800  0.75119700  0.50030900  1.0
  Li  Li1  1  0.33614000  0.24880800  0.50029100  1.0
  Li  Li2  1  0.66356700  0.74882700  0.50031700  1.0
  Li  Li3  1  0.83618600  0.25120500  0.50025600  1.0
  Fe  Fe4  1  0.00038600  0.99988100  0.99917800  1.0
  Fe  Fe5  1  0.50045000  0.50001600  0.99909400  1.0
  Co  Co6  1  0.33510800  0.99998100  0.32987000  1.0
  Co  Co7  1  0.83507700  0.49999900  0.32985000  1.0
  Co  Co8  1  0.16407000  0.50000800  0.67186200  1.0
  Co  Co9  1  0.66404400  0.00006000  0.67183700  1.0
  O  O10  1  0.16663200  0.59691500  0.99460700  1.0
  O  O11  1  0.33879400  0.09688100  0.99455800  1.0
  O  O12  1  0.66657300  0.90309000  0.99463900  1.0
  O  O13  1  0.83882400  0.40308700  0.99449500  1.0
  O  O14  1  0.99227900  0.89729100  0.34852300  1.0
  O  O15  1  0.15918900  0.39733700  0.34835500  1.0
  O  O16  1  0.49241800  0.60266900  0.34844700  1.0
  O  O17  1  0.65943600  0.10261600  0.34822700  1.0
  O  O18  1  0.00085800  0.10275100  0.65614800  1.0
  O  O19  1  0.34276400  0.89738400  0.65647600  1.0
  O  O20  1  0.50075200  0.39729900  0.65628600  1.0
  O  O21  1  0.84292700  0.60269800  0.65637600  1.0

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