ErFe4B

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-3045 · Space group: P6/mmm (#191)

Materials Project API

Basic Information

Formula

ErFe4B

MP-ID

mp-3045

Elements

Sites

Density

8.6412

g/cm³

Volume

154.29

Å³

Cell a

5.0357

Cell b

5.0357

Cell c

7.0256

α Angle

90.00

β Angle

90.00

γ Angle

120.00

Space Group

P6/mmm

Point Group

6/mmm

Crystal System

Hexagonal

Bravais Lattice

Stability

Yes

Packing Fraction

0.7405

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
12.60	7.0256	1.6	(0,0,0,1)
20.36	4.3611	22.0	(0,1,-1,0)
20.36	4.3611	22.0	(1,0,-1,0)
20.36	4.3611	22.0	(1,-1,0,0)
25.35	3.5128	13.7	(0,0,0,2)
32.74	2.7357	98.2	(0,1,-1,2)
32.74	2.7357	98.2	(1,0,-1,2)
32.74	2.7357	98.2	(1,-1,0,2)
35.66	2.5179	34.1	(1,1,-2,0)
35.66	2.5179	34.1	(1,-2,1,0)
35.66	2.5179	34.1	(2,-1,-1,0)
37.96	2.3703	7.8	(1,1,-2,1)
37.96	2.3703	7.8	(1,-2,1,1)
37.96	2.3702	7.8	(2,-1,-1,1)
38.44	2.3419	23.2	(0,0,0,3)
41.41	2.1806	71.3	(0,2,-2,0)
41.41	2.1805	71.3	(2,0,-2,0)
41.41	2.1805	71.3	(2,-2,0,0)
43.45	2.0825	5.2	(0,2,-2,1)
43.45	2.0825	5.2	(2,0,-2,1)
43.45	2.0825	5.2	(2,-2,0,1)
43.88	2.0632	4.7	(0,1,-1,3)
43.88	2.0632	4.7	(1,0,-1,3)
43.88	2.0632	4.7	(1,-1,0,3)

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Energy Properties

Formation Energy/atom

-0.25021

eV/atom

Energy/atom

-7.77141

eV/atom

Energy above Hull

0.0000

eV/atom

Uncorrected Energy

-16.6735

eV/atom

Volume/atom

12.86

Å³

c/a Ratio

1.3952

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

16.6392

μB

Mag. Ordering

Unknown

Mag. Sites

Magnetization/Volume

0.107840

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

Fe · 0.667

Element Family

3d-TM

Solute Fraction

0.333

Interstitial Fraction

0.167

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

0.8676

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

7.2129

J/mol·K

Ω Parameter

0.7705

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

19.294%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.2477

smaller = more stable mixing

VEC

7.833

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-17.778

kJ/mol; negative = exothermic mixing

Entropy Norm

0.7897

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.751

Family

Fe-rich Alloy

Matrix Element

Fe · 0.667

Related Tasks

Related computation task IDs (5)

aaadnduv aaadsqfx aaaeknco aaaeubyn aaafyify

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-3045

Reference Citation

The crystal structure and related material properties of ErFe4B were obtained from the Materials Project database (MP-ID: mp-3045, 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_ErFe4B
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.03569491
_cell_length_b   5.03573812
_cell_length_c   7.02555979
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   119.99968330
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ErFe4B
_chemical_formula_sum   'Er2 Fe8 B2'
_cell_volume   154.28918991
_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
  Er  Er0  1  0.00000000  0.00000000  0.00000000  1.0
  Er  Er1  1  0.00000000  0.00000000  0.50000000  1.0
  Fe  Fe2  1  0.33333254  0.66666809  0.00000000  1.0
  Fe  Fe3  1  0.00000000  0.50000000  0.71546153  1.0
  Fe  Fe4  1  0.50000000  0.00000000  0.28453702  1.0
  Fe  Fe5  1  0.66666746  0.33333191  0.00000000  1.0
  Fe  Fe6  1  0.50000000  0.50000000  0.28453847  1.0
  Fe  Fe7  1  0.50000000  0.00000000  0.71546298  1.0
  Fe  Fe8  1  0.00000000  0.50000000  0.28453847  1.0
  Fe  Fe9  1  0.50000000  0.50000000  0.71546153  1.0
  B  B10  1  0.33333395  0.66666790  0.50000000  1.0
  B  B11  1  0.66666605  0.33333210  0.50000000  1.0

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