KFePO4F

High-Entropy Materials HEA

MP-ID: mp-6834 · Space group: Pna2_1 (#33)

Materials Project API

Basic Information

Formula

KFePO4F

MP-ID

mp-6834

Elements

Sites

Density

3.0526

g/cm³

Volume

909.15

Å³

Cell a

6.4468

Cell b

10.8044

Cell c

13.0524

α Angle

90.00

β Angle

90.00

γ Angle

90.00

Space Group

Pna2_1

Point Group

mm2

Crystal System

Orthorhombic

Bravais Lattice

Orthorhombic 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
13.57	6.5262	27.2	(0,0,2)
15.33	5.7802	49.1	(1,0,1)
15.86	5.5862	95.9	(0,1,2)
16.01	5.5362	100.0	(1,1,0)
17.40	5.0967	4.5	(1,1,1)
21.04	4.2218	14.5	(1,1,2)
22.53	3.9468	1.2	(1,2,1)
24.69	3.6064	13.7	(1,0,3)
25.48	3.4963	54.1	(1,2,2)
26.05	3.4208	43.4	(1,1,3)
28.30	3.1532	68.0	(0,3,2)
28.39	3.1441	65.5	(1,3,0)
28.58	3.1238	2.8	(0,1,4)
29.22	3.0567	1.3	(1,3,1)
29.72	3.0058	9.9	(2,1,1)
29.79	2.9994	1.6	(1,2,3)
30.71	2.9114	1.5	(1,0,4)
30.94	2.8901	1.6	(2,0,2)
31.83	2.8111	93.1	(1,1,4)
32.04	2.7931	57.9	(0,2,4)
32.06	2.7919	65.9	(2,1,2)
32.34	2.7681	78.6	(2,2,0)
33.08	2.7079	1.7	(2,2,1)
33.17	2.7011	34.9	(0,4,0)

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Energy Properties

Formation Energy/atom

-2.33574

eV/atom

Energy/atom

-6.92615

eV/atom

Energy above Hull

0.2004

eV/atom

Uncorrected Energy

-6.2429

eV/atom

Volume/atom

14.21

Å³

c/a Ratio

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

1.8041

μB

Mag. Ordering

FiM

Mag. Sites

Magnetization/Volume

0.001980

μB/Å³

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

0.125

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.3863

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

11.5257

J/mol·K

Ω Parameter

1.6181

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

58.383%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

1.0161

smaller = more stable mixing

VEC

4.375

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-2.438

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8614

SS Former

Phase Tendency

Related Tasks

Related computation task IDs (1)

aaadwsii

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-6834

Reference Citation

The crystal structure and related material properties of KFePO4F were obtained from the Materials Project database (MP-ID: mp-6834, 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_KFePO4F
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.44680100
_cell_length_b   10.80440100
_cell_length_c   13.05242200
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   90.00000000
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KFePO4F
_chemical_formula_sum   'K8 Fe8 P8 O32 F8'
_cell_volume   909.15109394
_cell_formula_units_Z   8
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  0.77270400  0.20309100  0.37531900  1.0
  K  K1  1  0.30263100  0.94282800  0.89493400  1.0
  K  K2  1  0.80263100  0.44282800  0.60506600  1.0
  K  K3  1  0.19736900  0.94282800  0.39493400  1.0
  K  K4  1  0.69736900  0.44282800  0.10506600  1.0
  K  K5  1  0.27270400  0.70309100  0.12468100  1.0
  K  K6  1  0.72729600  0.20309100  0.87531900  1.0
  K  K7  1  0.22729600  0.70309100  0.62468100  1.0
  Fe  Fe8  1  0.75093900  0.74870400  0.25312700  1.0
  Fe  Fe9  1  0.24906100  0.24870400  0.74687300  1.0
  Fe  Fe10  1  0.74906100  0.74870400  0.75312700  1.0
  Fe  Fe11  1  0.25093900  0.24870400  0.24687300  1.0
  Fe  Fe12  1  0.49326500  0.49906200  0.38851700  1.0
  Fe  Fe13  1  0.50673500  0.99906200  0.61148300  1.0
  Fe  Fe14  1  0.00673500  0.49906200  0.88851700  1.0
  Fe  Fe15  1  0.99326500  0.99906200  0.11148300  1.0
  P  P16  1  0.99808600  0.49614500  0.31731800  1.0
  P  P17  1  0.49808600  0.99614500  0.18268200  1.0
  P  P18  1  0.50191400  0.49614500  0.81731800  1.0
  P  P19  1  0.00191400  0.99614500  0.68268200  1.0
  P  P20  1  0.16990600  0.24783000  0.99998100  1.0
  P  P21  1  0.83009400  0.74783000  0.00001900  1.0
  P  P22  1  0.33009400  0.24783000  0.49998100  1.0
  P  P23  1  0.66990600  0.74783000  0.50001900  1.0
  O  O24  1  0.30798200  0.96919600  0.11303900  1.0
  O  O25  1  0.81041400  0.02331000  0.61520800  1.0
  O  O26  1  0.31041400  0.52331000  0.88479200  1.0
  O  O27  1  0.68958600  0.02331000  0.11520800  1.0
  O  O28  1  0.03593800  0.38129000  0.24696100  1.0
  O  O29  1  0.96406200  0.88129000  0.75303900  1.0
  O  O30  1  0.46406200  0.38129000  0.74696100  1.0
  O  O31  1  0.53593800  0.88129000  0.25303900  1.0
  O  O32  1  0.51891500  0.85911300  0.51404200  1.0
  O  O33  1  0.48108500  0.35911300  0.48595800  1.0
  O  O34  1  0.98108500  0.85911300  0.01404200  1.0
  O  O35  1  0.01891500  0.35911300  0.98595800  1.0
  O  O36  1  0.80798200  0.46919600  0.38696100  1.0
  O  O37  1  0.19201800  0.96919600  0.61303900  1.0
  O  O38  1  0.69201800  0.46919600  0.88696100  1.0
  O  O39  1  0.18958600  0.52331000  0.38479200  1.0
  O  O40  1  0.52915000  0.63114800  0.48865900  1.0
  O  O41  1  0.47085000  0.13114800  0.51134100  1.0
  O  O42  1  0.97085000  0.63114800  0.98865900  1.0
  O  O43  1  0.45202200  0.10721300  0.25539400  1.0
  O  O44  1  0.80725500  0.76727900  0.40434700  1.0
  O  O45  1  0.19274500  0.26727900  0.59565300  1.0
  O  O46  1  0.69274500  0.76727900  0.90434700  1.0
  O  O47  1  0.30725500  0.26727900  0.09565300  1.0
  O  O48  1  0.69403000  0.72967800  0.09680000  1.0
  O  O49  1  0.30597000  0.22967800  0.90320000  1.0
  O  O50  1  0.80597000  0.72967800  0.59680000  1.0
  O  O51  1  0.19403000  0.22967800  0.40320000  1.0
  O  O52  1  0.95202200  0.60721300  0.24460600  1.0
  O  O53  1  0.04797800  0.10721300  0.75539400  1.0
  O  O54  1  0.54797800  0.60721300  0.74460600  1.0
  O  O55  1  0.02915000  0.13114800  0.01134100  1.0
  F  F56  1  0.98102300  0.86860800  0.22755500  1.0
  F  F57  1  0.01897700  0.36860800  0.77244500  1.0
  F  F58  1  0.51897700  0.86860800  0.72755500  1.0
  F  F59  1  0.48102300  0.36860800  0.27244500  1.0
  F  F60  1  0.02608500  0.11980600  0.23036800  1.0
  F  F61  1  0.97391500  0.61980600  0.76963200  1.0
  F  F62  1  0.47391500  0.11980600  0.73036800  1.0
  F  F63  1  0.52608500  0.61980600  0.26963200  1.0

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