Hf4Nb2Al7

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-3203463 · Space group: R-3m (#166)

Materials Project API

Basic Information

Formula

Hf4Nb2Al7

MP-ID

mp-3203463

Elements

Sites

Density

7.9727

g/cm³

Volume

226.74

Å³

Cell a

5.2395

Cell b

5.2395

Cell c

10.0056

α Angle

74.82

β Angle

74.82

γ Angle

60.00

Space Group

R-3m

Point Group

-3m

Crystal System

Trigonal

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
9.27	9.5373	21.1	(0,0,1)
18.61	4.7687	100.0	(0,0,2)
19.81	4.4815	8.2	(0,1,0)
19.81	4.4815	16.4	(1,1,1)
20.53	4.3252	8.1	(1,1,0)
20.53	4.3252	4.0	(1,0,1)
23.21	3.8316	28.3	(0,1,-1)
23.21	3.8316	56.5	(1,1,2)
25.05	3.5554	9.3	(1,1,-1)
29.41	3.0369	1.1	(0,1,-2)
29.41	3.0369	2.2	(1,1,3)
31.86	2.8089	1.2	(1,1,-2)
31.86	2.8089	2.4	(1,0,3)
34.23	2.6197	76.4	(1,2,1)
34.23	2.6197	76.4	(1,-1,0)
34.23	2.6197	76.4	(2,1,1)
35.54	2.5262	3.0	(1,2,0)
35.54	2.5262	3.0	(1,-1,1)
35.54	2.5262	3.0	(2,1,0)
37.15	2.4202	45.4	(0,1,-3)
37.15	2.4202	90.7	(1,0,-3)
37.73	2.3843	12.9	(0,0,4)
39.24	2.2961	33.1	(1,2,-1)
39.24	2.2961	99.3	(1,-1,2)

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Energy Properties

Formation Energy/atom

-0.50658

eV/atom

Energy/atom

-21.82954

eV/atom

Energy above Hull

0.0000

eV/atom

Uncorrected Energy

-21.8295

eV/atom

Volume/atom

17.44

Å³

c/a Ratio

1.9097

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Total Mag. Moment

0.0004

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.000000

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

Al · 0.538

Element Family

PostTransition-Noble

Solute Fraction

0.462

Interstitial Fraction

0.000

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

0.9840

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

8.1807

J/mol·K

Ω Parameter

0.4377

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

4.820%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.1421

smaller = more stable mixing

VEC

3.615

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-31.716

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8956

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.706

Family

Al-based Alloy

Matrix Element

Al · 0.538

Related Tasks

Related computation task IDs (1)

aaahagwd

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-3203463

Reference Citation

The crystal structure and related material properties of Hf4Nb2Al7 were obtained from the Materials Project database (MP-ID: mp-3203463, 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_Hf4Nb2Al7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.23945247
_cell_length_b   5.23945505
_cell_length_c   10.00554956
_cell_angle_alpha   74.82149349
_cell_angle_beta   74.82148589
_cell_angle_gamma   60.00000384
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Hf4Nb2Al7
_chemical_formula_sum   'Hf4 Nb2 Al7'
_cell_volume   226.74038180
_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
  Hf  Hf0  1  0.83463793  0.83463793  0.49608620  1.0
  Hf  Hf1  1  0.16536207  0.16536207  0.50391380  1.0
  Hf  Hf2  1  0.64868674  0.64868674  0.05393777  1.0
  Hf  Hf3  1  0.35131326  0.35131326  0.94606223  1.0
  Nb  Nb4  1  0.54402029  0.54402029  0.36793812  1.0
  Nb  Nb5  1  0.45597971  0.45597971  0.63206188  1.0
  Al  Al6  1  0.00000000  0.00000000  0.00000000  1.0
  Al  Al7  1  0.90797857  0.90797857  0.76974260  1.0
  Al  Al8  1  0.41429925  0.90797857  0.76974260  1.0
  Al  Al9  1  0.90797857  0.41429925  0.76974260  1.0
  Al  Al10  1  0.09202143  0.09202143  0.23025740  1.0
  Al  Al11  1  0.58570075  0.09202143  0.23025740  1.0
  Al  Al12  1  0.09202143  0.58570075  0.23025740  1.0

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