Li2FeCo3O8

High-Entropy Materials HEA

MP-ID: mp-861570 · Space group: R-3m (#166)

Materials Project API

Basic Information

Formula

Li2FeCo3O8

MP-ID

mp-861570

Elements

Sites

Density

4.5530

g/cm³

Volume

273.19

Å³

Cell a

5.7530

Cell b

5.8254

Cell c

9.9098

α Angle

106.41

β Angle

90.01

γ Angle

60.42

Space Group

R-3m

Point Group

-3m

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
18.52	4.7918	100.0	(0,1,0)
18.88	4.7008	67.5	(1,1,-1)
18.88	4.7006	67.5	(1,0,1)
18.94	4.6865	72.1	(0,0,2)
36.06	2.4904	11.2	(1,-1,-1)
36.07	2.4898	11.2	(1,2,1)
36.14	2.4852	11.7	(0,2,-2)
36.43	2.4666	11.8	(2,0,0)
36.44	2.4660	11.8	(2,2,0)
36.52	2.4605	12.2	(1,0,-3)
36.53	2.4598	12.2	(1,1,3)
36.57	2.4575	12.2	(1,2,-3)
36.57	2.4574	12.2	(1,-1,3)
36.65	2.4519	12.3	(2,1,-2)
36.66	2.4512	12.3	(2,1,2)
36.82	2.4409	10.8	(0,1,-4)
37.54	2.3959	11.2	(0,2,0)
38.29	2.3504	9.7	(2,2,-2)
38.30	2.3503	9.7	(2,0,2)
38.42	2.3433	9.5	(0,0,4)
44.26	2.0465	53.4	(2,0,-2)
44.28	2.0458	53.3	(2,2,2)
44.44	2.0384	52.2	(0,2,-4)
47.93	1.8981	3.0	(0,2,2)

Get direct link

Energy Properties

Formation Energy/atom

-1.56240

eV/atom

Energy/atom

-6.79610

eV/atom

Energy above Hull

0.0010

eV/atom

Uncorrected Energy

-5.8914

eV/atom

Volume/atom

9.76

Å³

c/a Ratio

1.7225

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

9.9967

μB

Mag. Ordering

FiM

Mag. Sites

Magnetization/Volume

0.036590

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

O · 0.571

Element Family

Metalloid-Nonmetal

Solute Fraction

0.429

Interstitial Fraction

0.000

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.1164

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

9.2815

J/mol·K

Ω Parameter

0.9573

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

40.987%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.9644

smaller = more stable mixing

VEC

4.929

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-5.860

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8053

SS Former

Phase Tendency

Related Tasks

Related computation task IDs (2)

aaabxdoi aaaczojm

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-861570

Reference Citation

The crystal structure and related material properties of Li2FeCo3O8 were obtained from the Materials Project database (MP-ID: mp-861570, 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…

Style: Ball & Stick | Drag to rotate · Scroll to zoom · Right-click to pan

Raw CIF Data

# generated using pymatgen
data_Li2FeCo3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.75302753
_cell_length_b   5.82539009
_cell_length_c   9.90980887
_cell_angle_alpha   106.40688263
_cell_angle_beta   90.01376291
_cell_angle_gamma   60.42083435
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Li2FeCo3O8
_chemical_formula_sum   'Li4 Fe2 Co6 O16'
_cell_volume   273.18621982
_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  0.68467400  0.63072500  0.43481300  1.0
  Li  Li1  1  0.18390100  0.63216300  0.93542400  1.0
  Li  Li2  1  0.81531900  0.36928800  0.06518300  1.0
  Li  Li3  1  0.31609600  0.36784200  0.56457700  1.0
  Fe  Fe4  1  0.75002000  0.49995500  0.74982300  1.0
  Fe  Fe5  1  0.24999600  0.50001600  0.25013900  1.0
  Co  Co6  1  0.00012800  0.99978700  0.49988800  1.0
  Co  Co7  1  0.24997100  0.00001100  0.25000700  1.0
  Co  Co8  1  0.75001900  0.00000700  0.25001000  1.0
  Co  Co9  1  0.49989100  0.00017500  0.00007100  1.0
  Co  Co10  1  0.74999600  0.99999300  0.75003100  1.0
  Co  Co11  1  0.25001300  0.99999300  0.75002900  1.0
  O  O12  1  0.60416300  0.79161200  0.13173000  1.0
  O  O13  1  0.10428900  0.79149400  0.63256700  1.0
  O  O14  1  0.89583300  0.20839700  0.36827600  1.0
  O  O15  1  0.39571500  0.20849700  0.86744100  1.0
  O  O16  1  0.38060600  0.78041000  0.87011400  1.0
  O  O17  1  0.88292800  0.77802600  0.36864500  1.0
  O  O18  1  0.60710500  0.78584200  0.64463300  1.0
  O  O19  1  0.10596600  0.78796300  0.14490200  1.0
  O  O20  1  0.83865600  0.78081000  0.87022200  1.0
  O  O21  1  0.33905800  0.77814400  0.36868700  1.0
  O  O22  1  0.66126700  0.21913900  0.62973300  1.0
  O  O23  1  0.16099200  0.22190600  0.13135400  1.0
  O  O24  1  0.89287100  0.21420400  0.85530900  1.0
  O  O25  1  0.39402900  0.21204000  0.35515900  1.0
  O  O26  1  0.11952000  0.21954000  0.62984100  1.0
  O  O27  1  0.61697600  0.22202200  0.13139400  1.0

Get direct link