Li9(FeO4)2

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-759144 · Space group: Pc (#7)

Materials Project API

Basic Information

Formula

Li9(FeO4)2

MP-ID

mp-759144

Elements

Sites

Density

2.4872

g/cm³

Volume

403.46

Å³

Cell a

6.8155

Cell b

5.4992

Cell c

11.2397

α Angle

73.28

β Angle

90.00

γ Angle

90.00

Space Group

Point Group

Crystal System

Monoclinic

Bravais Lattice

Monoclinic P

Stability

Packing Fraction

0.5240

X-ray Diffraction

Diffraction Pattern

Target / Radiation

X-axis: 2θ (°); Y-axis: relative intensity; CuKa ; λ=1.5406 Å

Diffraction Peaks (Top 24)

2θ	d (Å)	I	hkl
15.39	5.7584	2.1	(1,0,1)
16.47	5.3823	37.5	(0,0,2)
16.83	5.2667	31.0	(0,1,0)
21.03	4.2240	57.4	(1,0,2)
21.03	4.2235	1.1	(1,1,1)
21.32	4.1674	55.3	(1,1,0)
23.84	3.7320	100.0	(1,1,2)
24.60	3.6189	2.8	(1,1,-1)
26.15	3.4078	28.5	(2,0,0)
26.88	3.3173	24.9	(0,1,-2)
31.06	2.8792	11.0	(2,0,2)
31.06	2.8791	1.2	(2,1,1)
31.26	2.8611	17.0	(2,1,0)
32.72	2.7366	4.2	(0,1,4)
33.08	2.7078	41.0	(2,1,2)
33.29	2.6911	14.0	(0,0,4)
33.30	2.6907	3.8	(0,2,2)
34.05	2.6334	13.9	(0,2,0)
35.34	2.5395	15.3	(1,1,4)
35.88	2.5031	15.9	(1,0,4)
35.88	2.5027	17.2	(1,2,2)
36.58	2.4564	17.0	(1,2,0)
37.85	2.3770	2.3	(2,1,-2)
41.86	2.1580	4.5	(0,1,-4)

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Energy Properties

Formation Energy/atom

-1.90683

eV/atom

Energy/atom

-5.78599

eV/atom

Energy above Hull

0.0887

eV/atom

Uncorrected Energy

-5.2593

eV/atom

Volume/atom

10.62

Å³

c/a Ratio

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

17.9980

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.044610

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

Li · 0.474

Element Family

Alkali-AlkEarth

Solute Fraction

0.526

Interstitial Fraction

0.000

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

0.9551

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

7.9410

J/mol·K

Ω Parameter

1.7065

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

39.592%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

1.1653

smaller = more stable mixing

VEC

3.000

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

1.994

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8694

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.388

Family

Li-rich Multi-Component

Matrix Element

Li · 0.474

Related Tasks

Related computation task IDs (2)

aaabyyle aaadzlxo

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-759144

Reference Citation

The crystal structure and related material properties of Li9(FeO4)2 were obtained from the Materials Project database (MP-ID: mp-759144, 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

BibTeX

@article{Horton2025,
  author  = {Horton, Matthew K. and Huck, Patrick and Yang, Ruo Xi and Munro, Jason M. and Dwaraknath, Shyam and Ganose, Alex M. and Kingsbury, Ryan S. and Wen, Mingjian and Shen, Jimmy X. and Mathis, Tyler S. and Kaplan, Aaron D. and Berket, Karlo and Riebesell, Janosh and George, Janine and Rosen, Andrew S. and Spotte-Smith, Evan W. C. and McDermott, Matthew J. and Cohen, Orion A. and Dunn, Alex and Kuner, Matthew C. and Rignanese, Gian-Marco and Petretto, Guido and Waroquiers, David and Griffin, Sinead M. and Neaton, Jeffrey B. and Chrzan, Daryl C. and Asta, Mark and Hautier, Geoffroy and Cholia, Shreyas and Ceder, Gerbrand and Ong, Shyue Ping and Jain, Anubhav and Persson, Kristin A.},
  title   = {Accelerated data-driven materials science with the Materials Project},
  journal = {Nature Materials},
  year    = {2025},
  volume  = {24},
  number  = {10},
  pages   = {1522--1532},
  month   = {oct},
  doi     = {10.1038/s41563-025-02272-0},
  issn    = {1476-4660},
  url     = {https://doi.org/10.1038/s41563-025-02272-0},
  abstract = {The Materials Project was launched formally in 2011 to drive materials discovery forwards through high-throughput computation and open data. More than a decade later, the Materials Project has become an indispensable tool used by more than 600,000 materials researchers around the world. This Perspective describes how the Materials Project, as a data platform and a software ecosystem, has helped to shape research in data-driven materials science. We cover how sustainable software and computational methods have accelerated materials design while becoming more open source and collaborative in nature. Next, we present cases where the Materials Project was used to understand and discover functional materials. We then describe our efforts to meet the needs of an expanding user base, through technical infrastructure updates ranging from data architecture and cloud resources to interactive web applications. Finally, we discuss opportunities to better aid the research community, with the vision that more accessible and easy-to-understand materials data will result in democratized materials knowledge and an increasingly collaborative community.}
}

3D Crystal Structure Rendering

Loading 3D structure…

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Raw CIF Data

# generated using pymatgen
data_Li9(FeO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.81552900
_cell_length_b   5.49924400
_cell_length_c   11.23974468
_cell_angle_alpha   73.27893338
_cell_angle_beta   90.00000000
_cell_angle_gamma   90.00000000
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Li9(FeO4)2
_chemical_formula_sum   'Li18 Fe4 O16'
_cell_volume   403.45592620
_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  0.04599300  0.37302600  0.71970900  1.0
  Li  Li1  1  0.00022400  0.66326300  0.33891700  1.0
  Li  Li2  1  0.72045900  0.36028900  0.93974900  1.0
  Li  Li3  1  0.22580700  0.63448000  0.56185900  1.0
  Li  Li4  1  0.78658500  0.63496900  0.57146700  1.0
  Li  Li5  1  0.73051200  0.91470700  0.19907100  1.0
  Li  Li6  1  0.50806800  0.60037100  0.79355100  1.0
  Li  Li7  1  0.99977600  0.66326300  0.83891700  1.0
  Li  Li8  1  0.21258600  0.08892600  0.30307800  1.0
  Li  Li9  1  0.26948800  0.91470700  0.69907100  1.0
  Li  Li10  1  0.49248000  0.31463600  0.15844800  1.0
  Li  Li11  1  0.95400700  0.37302600  0.21970900  1.0
  Li  Li12  1  0.78741400  0.08892600  0.80307800  1.0
  Li  Li13  1  0.27954100  0.36028900  0.43974900  1.0
  Li  Li14  1  0.77419300  0.63448000  0.06185900  1.0
  Li  Li15  1  0.21341500  0.63496900  0.07146700  1.0
  Li  Li16  1  0.50752000  0.31463600  0.65844800  1.0
  Li  Li17  1  0.49193200  0.60037100  0.29355100  1.0
  Fe  Fe18  1  0.50697600  0.89675900  0.43919500  1.0
  Fe  Fe19  1  0.01504500  0.12363200  0.05632900  1.0
  Fe  Fe20  1  0.49302400  0.89675900  0.93919500  1.0
  Fe  Fe21  1  0.98495500  0.12363200  0.55632900  1.0
  O  O22  1  0.53423200  0.22609500  0.84624000  1.0
  O  O23  1  0.97420700  0.27525400  0.88672400  1.0
  O  O24  1  0.72137900  0.76460500  0.37921500  1.0
  O  O25  1  0.28273900  0.73815500  0.38634200  1.0
  O  O26  1  0.49315800  0.72736900  0.61037700  1.0
  O  O27  1  0.02269500  0.76858700  0.64349800  1.0
  O  O28  1  0.27862100  0.76460500  0.87921500  1.0
  O  O29  1  0.71726100  0.73815500  0.88634200  1.0
  O  O30  1  0.77324200  0.26030100  0.11340200  1.0
  O  O31  1  0.20289700  0.27234400  0.13199800  1.0
  O  O32  1  0.46576800  0.22609500  0.34624000  1.0
  O  O33  1  0.02579300  0.27525400  0.38672400  1.0
  O  O34  1  0.22675800  0.26030100  0.61340200  1.0
  O  O35  1  0.79710300  0.27234400  0.63199800  1.0
  O  O36  1  0.50684200  0.72736900  0.11037700  1.0
  O  O37  1  0.97730500  0.76858700  0.14349800  1.0

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