HfCoAs

高熵材料 HEA 传统材料 TRA 弹性数据 ELA

MP-ID: mp-9801 · Space group: Pnma (#62)

Materials Project API

Basic Information

Formula

HfCoAs

MP-ID

mp-9801

Elements

Sites

Density

11.8416

g/cm³

Volume

175.20

Å³

Cell a

3.7952

Cell b

6.4227

Cell c

7.1877

α Angle

90.00

β Angle

90.00

γ Angle

90.00

Space Group

Pnma

Point Group

mmm

Crystal System

Orthorhombic

Bravais Lattice

Stability

Yes

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
18.53	4.7892	3.4	(0,1,1)
24.77	3.5938	8.8	(0,0,2)
26.56	3.3561	22.3	(1,0,1)
27.78	3.2113	9.5	(0,2,0)
28.46	3.1362	1.9	(0,1,2)
30.04	2.9745	2.1	(1,1,1)
30.49	2.9320	1.5	(0,2,1)
36.66	2.4515	9.6	(1,2,0)
37.19	2.4176	65.0	(1,1,2)
37.56	2.3946	23.2	(0,2,2)
38.81	2.3202	100.0	(1,2,1)
40.17	2.2448	29.5	(0,1,3)
44.14	2.0518	13.4	(0,3,1)
44.73	2.0260	26.6	(1,0,3)
47.03	1.9321	8.0	(1,1,3)
47.34	1.9203	2.1	(0,2,3)
47.94	1.8976	30.1	(2,0,0)
49.56	1.8393	10.5	(0,3,2)
50.57	1.8049	3.6	(1,3,1)
50.81	1.7969	1.5	(0,0,4)
54.70	1.6780	2.3	(2,0,2)
55.52	1.6551	2.3	(1,3,2)
56.31	1.6337	2.9	(2,2,0)
57.39	1.6057	5.1	(0,4,0)

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Energy Properties

Formation Energy/atom

-0.80395

eV/atom

Energy/atom

-8.05753

eV/atom

Energy above Hull

0.0000

eV/atom

Uncorrected Energy

-25.1607

eV/atom

Volume/atom

14.60

Å³

c/a Ratio

1.8939

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

0.0014

μB

Mag. Ordering

Unknown

Mag. Sites

Magnetization/Volume

0.000010

μB/Å³

Elastic Properties

K_VRH

177.383

GPa

G_VRH

92.377

GPa

Young's Modulus E

236.139

GPa

Poisson Ratio ν

0.278

Pugh Ratio K/G

1.920

Vickers Hardness Est.

GPa

Ductility

Brittle

Anisotropy

0.117

Lame λ

115.798

GPa

Feature Analysis

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

Hf · 0.333

Element Family

5d-TM

Solute Fraction

0.667

Interstitial Fraction

0.000

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

1.0079

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

14.160%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.3653

smaller = more stable mixing

VEC

5.333

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-16.203

kJ/mol; negative = exothermic mixing

Entropy Norm

1.0000

SS Former

Phase Tendency

Related Tasks

Related computation task IDs (5)

aaadndog aaadsmdu aaaemvkx aaaergmb aaafcptg

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-9801

Reference Citation

The crystal structure and related material properties of HfCoAs were obtained from the Materials Project database (MP-ID: mp-9801, 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_HfCoAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.79517913
_cell_length_b   6.42264666
_cell_length_c   7.18765567
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   90.00000000
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfCoAs
_chemical_formula_sum   'Hf4 Co4 As4'
_cell_volume   175.19978665
_cell_formula_units_Z   4
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  0.25000000  0.51914567  0.81238678  1.0
  Hf  Hf1  1  0.75000000  0.48085433  0.18761322  1.0
  Hf  Hf2  1  0.25000000  0.01914567  0.68761322  1.0
  Hf  Hf3  1  0.75000000  0.98085433  0.31238678  1.0
  Co  Co4  1  0.25000000  0.63848224  0.43616397  1.0
  Co  Co5  1  0.75000000  0.36151776  0.56383603  1.0
  Co  Co6  1  0.25000000  0.13848224  0.06383603  1.0
  Co  Co7  1  0.75000000  0.86151776  0.93616397  1.0
  As  As8  1  0.75000000  0.73165207  0.61473337  1.0
  As  As9  1  0.25000000  0.26834793  0.38526663  1.0
  As  As10  1  0.75000000  0.23165207  0.88526663  1.0
  As  As11  1  0.25000000  0.76834793  0.11473337  1.0

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