HfAsOs

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-1079823 · Space group: P-62m (#189)

Materials Project API

Basic Information

Formula

HfAsOs

MP-ID

mp-1079823

Elements

Sites

Density

14.7489

g/cm³

Volume

149.85

Å³

Cell a

6.5918

Cell b

6.5918

Cell c

3.9821

α Angle

90.00

β Angle

90.00

γ Angle

120.00

Space Group

P-62m

Point Group

-6m2

Crystal System

Hexagonal

Bravais Lattice

Stability

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
15.52	5.7086	2.9	(1,0,-1,0)
22.33	3.9821	1.3	(0,0,0,1)
27.05	3.2959	5.6	(2,-1,-1,0)
27.31	3.2660	11.6	(1,0,-1,1)
31.34	2.8543	4.5	(2,0,-2,0)
35.35	2.5390	100.0	(2,-1,-1,1)
38.82	2.3199	79.9	(2,0,-2,1)
41.87	2.1577	59.4	(3,-1,-2,0)
45.56	1.9911	29.8	(0,0,0,2)
47.80	1.9029	13.6	(3,0,-3,0)
47.95	1.8971	17.2	(3,-1,-2,1)
53.79	1.7042	1.9	(2,-1,-1,2)
55.78	1.6479	1.5	(4,-2,-2,0)
56.34	1.6330	1.7	(2,0,-2,2)
58.28	1.5833	2.8	(4,-3,-1,0)
58.28	1.5833	5.5	(4,-1,-3,0)
60.83	1.5227	2.7	(4,-2,-2,1)
63.20	1.4713	6.8	(4,-3,-1,1)
63.20	1.4713	13.6	(4,-1,-3,1)
63.59	1.4632	35.0	(3,-1,-2,2)
65.39	1.4272	6.0	(4,0,-4,0)
68.17	1.3757	9.4	(3,0,-3,2)
70.03	1.3435	4.3	(4,0,-4,1)
72.12	1.3097	2.3	(5,-2,-3,0)

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Energy Properties

Formation Energy/atom

-0.55486

eV/atom

Energy/atom

-9.17309

eV/atom

Energy above Hull

0.1065

eV/atom

Uncorrected Energy

-9.1731

eV/atom

Volume/atom

16.65

Å³

c/a Ratio

0.6041

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Total Mag. Moment

0.0015

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.000010

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

Hf · 0.333

Element Family

5d-TM

Solute Fraction

0.667

Interstitial Fraction

0.000

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.0986

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

9.1339

J/mol·K

Ω Parameter

1.1073

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

13.194%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.4196

smaller = more stable mixing

VEC

5.000

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-18.977

kJ/mol; negative = exothermic mixing

Entropy Norm

1.0000

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.319

Family

Hf-rich Multi-Component

Matrix Element

Hf · 0.333

Related Tasks

Related computation task IDs (5)

aaaddonb aaadmruj aaadswfj aaaeupdt aaafjjzs

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-1079823

Reference Citation

The crystal structure and related material properties of HfAsOs were obtained from the Materials Project database (MP-ID: mp-1079823, 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_HfAsOs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.59174644
_cell_length_b   6.59174644
_cell_length_c   3.98210200
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   120.00000442
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfAsOs
_chemical_formula_sum   'Hf3 As3 Os3'
_cell_volume   149.84559452
_cell_formula_units_Z   3
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
  Hf  Hf0  1  0.41964800  0.41964800  0.50000000  1.0
  Hf  Hf1  1  0.58035200  0.00000000  0.50000000  1.0
  Hf  Hf2  1  0.00000000  0.58035200  0.50000000  1.0
  As  As3  1  0.66666700  0.33333300  0.00000000  1.0
  As  As4  1  0.33333300  0.66666700  0.00000000  1.0
  As  As5  1  0.00000000  0.00000000  0.50000000  1.0
  Os  Os6  1  0.75326300  0.75326300  0.00000000  1.0
  Os  Os7  1  0.24673700  0.00000000  0.00000000  1.0
  Os  Os8  1  0.00000000  0.24673700  0.00000000  1.0

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