SrEu2Al2O7

High-Entropy Materials HEA

MP-ID: mp-983228 · Space group: I4/mmm (#139)

Materials Project API

Basic Information

Formula

SrEu2Al2O7

MP-ID

mp-983228

Elements

Sites

Density

6.7370

g/cm³

Volume

137.41

Å³

Cell a

10.2613

Cell b

10.2613

Cell c

10.2613

α Angle

159.10

β Angle

159.10

γ Angle

29.72

Space Group

I4/mmm

Point Group

4/mmm

Crystal System

Tetragonal

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
8.92	9.9180	23.2	(1,1,-1)
24.33	3.6584	35.8	(1,0,-1)
26.97	3.3060	26.0	(3,3,-3)
27.50	3.2436	44.5	(2,1,-2)
33.00	2.7145	100.0	(3,2,-3)
34.06	2.6320	71.6	(1,-1,0)
35.28	2.5440	10.0	(2,0,-1)
36.23	2.4795	5.5	(4,4,-4)
38.73	2.3249	3.7	(3,1,-2)
39.99	2.2547	4.0	(4,3,-4)
43.97	2.0591	52.0	(4,2,-3)
45.74	1.9836	11.0	(5,5,-5)
47.97	1.8965	8.9	(5,4,-5)
48.94	1.8611	41.6	(1,-1,1)
49.85	1.8292	1.8	(2,0,-2)
50.57	1.8048	13.6	(5,3,-4)
55.39	1.6588	8.5	(2,-1,-1)
55.60	1.6530	3.2	(6,6,-6)
56.72	1.6229	18.1	(6,5,-6)
56.76	1.6218	13.8	(4,2,-4)
57.05	1.6143	12.2	(3,0,-2)
58.24	1.5841	9.7	(6,4,-5)
60.30	1.5350	37.1	(4,1,-3)
62.39	1.4885	4.7	(5,3,-5)

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Energy Properties

Formation Energy/atom

-3.30511

eV/atom

Energy/atom

-8.67140

eV/atom

Energy above Hull

0.1480

eV/atom

Uncorrected Energy

-15.5281

eV/atom

Volume/atom

11.45

Å³

c/a Ratio

1.0000

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

12.0023

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.087340

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

O · 0.583

Element Family

Metalloid-Nonmetal

Solute Fraction

0.417

Interstitial Fraction

0.000

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.1187

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

9.3012

J/mol·K

Ω Parameter

0.0000

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

53.522%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

1.0613

smaller = more stable mixing

VEC

4.167

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

0.000

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8070

SS Former

Phase Tendency

Related Tasks

Related computation task IDs (4)

aaadogdd aaadulop aaaeqiox aaagitqa

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-983228

Reference Citation

The crystal structure and related material properties of SrEu2Al2O7 were obtained from the Materials Project database (MP-ID: mp-983228, 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_SrEu2Al2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.26132656
_cell_length_b   10.26132656
_cell_length_c   10.26132656
_cell_angle_alpha   159.10063022
_cell_angle_beta   159.10063022
_cell_angle_gamma   29.72482099
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SrEu2Al2O7
_chemical_formula_sum   'Sr1 Eu2 Al2 O7'
_cell_volume   137.41459648
_cell_formula_units_Z   1
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
  Sr  Sr0  1  0.50000000  0.50000000  -0.00000000  1.0
  Eu  Eu1  1  0.31867616  0.31867616  -0.00000000  1.0
  Eu  Eu2  1  0.68132384  0.68132384  0.00000000  1.0
  Al  Al3  1  0.90539746  0.90539746  -0.00000000  1.0
  Al  Al4  1  0.09460254  0.09460254  0.00000000  1.0
  O  O5  1  -0.00000000  -0.00000000  0.00000000  1.0
  O  O6  1  0.39798081  0.89798081  0.50000000  1.0
  O  O7  1  0.89798081  0.39798081  0.50000000  1.0
  O  O8  1  0.79975876  0.79975876  -0.00000000  1.0
  O  O9  1  0.20024124  0.20024124  0.00000000  1.0
  O  O10  1  0.10201919  0.60201919  0.50000000  1.0
  O  O11  1  0.60201919  0.10201919  0.50000000  1.0

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