Sr2Ho2As7Ir8
High-Entropy Materials HEAMP-ID: mp-3292398 · Space group: P2_1/m (#11)
Basic Information
Formula
Sr2Ho2As7Ir8
MP-ID
mp-3292398
Elements
4
Sites
38
Density
11.8468
g/cm³
Volume
719.70
ų
Cell a
4.0685
Å
Cell b
13.0869
Å
Cell c
13.6645
Å
α Angle
81.58
°
β Angle
90.00
°
γ Angle
90.00
°
Space Group
P2_1/m
Point Group
2/m
Crystal System
Monoclinic
Bravais Lattice
mP
Stability
Yes
Packing Fraction
-
X-ray Diffraction
Diffraction Pattern
X-axis: 2θ (°); Y-axis: relative intensity; Cu Kα ; λ=1.5418 Å
Diffraction Peaks (Top 24)
| 2θ | d (Å) | I | hkl |
|---|---|---|---|
| 6.54 | 13.5171 | 50.2 | (0,0,1) |
| 6.83 | 12.9457 | 18.5 | (0,1,0) |
| 8.74 | 10.1193 | 2.2 | (0,1,1) |
| 10.13 | 8.7322 | 1.3 | (0,1,-1) |
| 13.10 | 6.7585 | 19.7 | (0,0,2) |
| 13.68 | 6.4729 | 31.9 | (0,2,0) |
| 13.86 | 6.3874 | 5.2 | (0,1,2) |
| 14.28 | 6.2027 | 4.3 | (0,2,1) |
| 15.65 | 5.6606 | 1.9 | (0,1,-2) |
| 16.02 | 5.5309 | 24.3 | (0,2,-1) |
| 17.53 | 5.0597 | 1.1 | (0,2,2) |
| 19.70 | 4.5057 | 1.6 | (0,0,3) |
| 19.89 | 4.4631 | 29.4 | (0,1,3) |
| 20.34 | 4.3661 | 3.0 | (0,2,-2) |
| 20.58 | 4.3152 | 13.2 | (0,3,0) |
| 20.67 | 4.2973 | 5.1 | (0,3,1) |
| 21.82 | 4.0741 | 1.1 | (0,1,-3) |
| 22.33 | 3.9816 | 1.3 | (0,2,3) |
| 22.91 | 3.8813 | 1.0 | (1,1,0) |
| 23.57 | 3.7748 | 3.2 | (1,1,1) |
| 24.13 | 3.6879 | 3.3 | (1,1,-1) |
| 25.69 | 3.4675 | 11.4 | (0,2,-3) |
| 26.08 | 3.4171 | 5.4 | (0,3,-2) |
| 26.20 | 3.4020 | 1.3 | (1,2,1) |
Energy Properties
Formation Energy/atom
-0.82076
eV/atom
Energy/atom
-33.34084
eV/atom
Energy above Hull
0.0000
eV/atom
Uncorrected Energy
-33.3408
eV/atom
Volume/atom
18.94
ų
c/a Ratio
3.3586
Electronic Properties
Metallic
Metal
Band Gap
0
eV
Direct Gap
No
CBM
N/A
eV
Magnetic Properties
Magnetic
No
Total Mag. Moment
0.0171
μB
Mag. Ordering
NM
Mag. Sites
0
Magnetization/Volume
0.000020
μB/ų
Elastic Properties
Elastic data not available
Feature Analysis
Composition Overview
Element Composition (atomic fraction)
Composition Info
Major / Matrix Element
Ir · 0.421
Element Family
5d-TM
Solute Fraction
0.579
Interstitial Fraction
0.000
High-Entropy Alloy Features
Composite Radar (normalized)
Element-Class Share
Mix Entropy ΔS/R
1.2060
HEA criterion (>1.0 = high entropy)
Mix Entropy ΔS
10.0271
J/mol·K
Ω Parameter
0.0000
Ω > 1.1 favors solid solution
Atomic Size Mismatch δr
19.610%
δr < 6.6% favors single-phase solid solution
Electronegativity Diff Δχ
0.4534
smaller = more stable mixing
VEC
6.263
valence electron concentration, affects phase stability
Mix Enthalpy ΔH_mix
0.000
kJ/mol; negative = exothermic mixing
Entropy Norm
0.8700
SS Former
0
Phase Tendency
IM
Related Tasks
Related computation task IDs (1)
Citation & References
Materials Project Page
https://materialsproject.org/materials/mp-3292398
Reference Citation
The crystal structure and related material properties of Sr2Ho2As7Ir8 were obtained from the Materials Project database (MP-ID: mp-3292398, 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_Sr2Ho2As7Ir8
_symmetry_space_group_name_H-M 'P 1'
_cell_length_a 4.06849055
_cell_length_b 13.08692057
_cell_length_c 13.66448128
_cell_angle_alpha 81.57588345
_cell_angle_beta 90.00000000
_cell_angle_gamma 90.00000000
_symmetry_Int_Tables_number 1
_chemical_formula_structural Sr2Ho2As7Ir8
_chemical_formula_sum 'Sr4 Ho4 As14 Ir16'
_cell_volume 719.70208017
_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
Sr Sr0 1 0.25000000 0.10514138 0.79006013 1.0
Sr Sr1 1 0.75000000 0.89485862 0.20993987 1.0
Sr Sr2 1 0.25000000 0.28515418 0.10231959 1.0
Sr Sr3 1 0.75000000 0.71484582 0.89768041 1.0
Ho Ho4 1 0.25000000 0.51734003 0.29276512 1.0
Ho Ho5 1 0.75000000 0.48265997 0.70723488 1.0
Ho Ho6 1 0.25000000 0.20903568 0.44093112 1.0
Ho Ho7 1 0.75000000 0.79096432 0.55906888 1.0
As As8 1 0.25000000 0.05659237 0.10269900 1.0
As As9 1 0.75000000 0.94340763 0.89730100 1.0
As As10 1 0.25000000 0.31650596 0.68567288 1.0
As As11 1 0.75000000 0.68349404 0.31432712 1.0
As As12 1 0.25000000 0.60803924 0.56574201 1.0
As As13 1 0.75000000 0.39196076 0.43425799 1.0
As As14 1 0.25000000 0.84183124 0.71822209 1.0
As As15 1 0.75000000 0.15816876 0.28177791 1.0
As As16 1 0.75000000 0.25810330 0.91730646 1.0
As As17 1 0.25000000 0.74189670 0.08269354 1.0
As As18 1 0.75000000 0.09368487 0.58643166 1.0
As As19 1 0.25000000 0.90631513 0.41356834 1.0
As As20 1 0.75000000 0.46820856 0.12862887 1.0
As As21 1 0.25000000 0.53179144 0.87137113 1.0
Ir Ir22 1 0.25000000 0.98213029 0.57275877 1.0
Ir Ir23 1 0.75000000 0.01786971 0.42724123 1.0
Ir Ir24 1 0.25000000 0.65898766 0.72458458 1.0
Ir Ir25 1 0.75000000 0.34101234 0.27541542 1.0
Ir Ir26 1 0.25000000 0.55105135 0.05147330 1.0
Ir Ir27 1 0.75000000 0.44894865 0.94852670 1.0
Ir Ir28 1 0.25000000 0.06157603 0.28109733 1.0
Ir Ir29 1 0.75000000 0.93842397 0.71890267 1.0
Ir Ir30 1 0.25000000 0.42464904 0.52254224 1.0
Ir Ir31 1 0.75000000 0.57535096 0.47745776 1.0
Ir Ir32 1 0.25000000 0.91974412 0.99774188 1.0
Ir Ir33 1 0.75000000 0.08025588 0.00225812 1.0
Ir Ir34 1 0.25000000 0.72256449 0.40412867 1.0
Ir Ir35 1 0.75000000 0.27743551 0.59587133 1.0
Ir Ir36 1 0.25000000 0.34766500 0.85567471 1.0
Ir Ir37 1 0.75000000 0.65233500 0.14432529 1.0
