AlCr3B4

High-Entropy Materials HEA Traditional Materials TRA Elasticity Data ELA

MP-ID: mp-637575 · Space group: Pmmm (#47)

Materials Project API

Basic Information

Formula

AlCr3B4

MP-ID

mp-637575

Elements

Sites

Density

5.4684

g/cm³

Volume

68.69

Å³

Cell a

2.9209

Cell b

2.9184

Cell c

8.0583

α Angle

90.00

β Angle

90.00

γ Angle

90.00

Space Group

Pmmm

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
10.98	8.0583	9.0	(0,0,1)
22.06	4.0291	4.4	(0,0,2)
30.61	2.9209	41.4	(1,0,0)
30.63	2.9184	2.9	(0,1,0)
32.61	2.7461	7.6	(1,0,1)
32.63	2.7440	16.2	(0,1,1)
33.36	2.6861	29.8	(0,0,3)
38.05	2.3649	11.1	(1,0,2)
38.07	2.3635	100.0	(0,1,2)
43.85	2.0645	18.5	(1,1,0)
45.00	2.0146	18.0	(0,0,4)
45.35	1.9999	75.6	(1,1,1)
45.90	1.9772	78.2	(1,0,3)
45.92	1.9764	8.4	(0,1,3)
49.62	1.8374	64.9	(1,1,2)
55.40	1.6584	5.6	(1,0,4)
55.42	1.6579	6.0	(0,1,4)
57.15	1.6117	4.3	(0,0,5)
63.72	1.4605	19.4	(2,0,0)
63.78	1.4592	19.3	(0,2,0)
64.64	1.4419	2.2	(1,1,4)
66.25	1.4108	17.3	(0,1,5)
70.06	1.3431	2.5	(0,0,6)
72.40	1.3054	5.6	(1,2,0)

Get direct link

Energy Properties

Formation Energy/atom

-0.36288

eV/atom

Energy/atom

-10.53007

eV/atom

Energy above Hull

0.0000

eV/atom

Uncorrected Energy

-10.5301

eV/atom

Volume/atom

8.59

Å³

c/a Ratio

2.7588

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

0.5736

μB

Mag. Ordering

Unknown

Mag. Sites

Magnetization/Volume

0.008350

μB/Å³

Elastic Properties

K_VRH

248.749

GPa

G_VRH

182.763

GPa

Young's Modulus E

440.425

GPa

Poisson Ratio ν

0.205

Pugh Ratio K/G

1.361

Vickers Hardness Est.

26.350

GPa

Ductility

Ductile

Anisotropy

0.040

Lame λ

126.907

GPa

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

B · 0.500

Element Family

Metalloid-Nonmetal

Solute Fraction

0.500

Interstitial Fraction

0.500

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

0.9743

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

8.1005

J/mol·K

Ω Parameter

0.4079

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

19.278%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.1968

smaller = more stable mixing

VEC

4.125

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-41.875

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8869

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.530

Family

Interstitial Alloy

Matrix Element

B · 0.500

Elasticity Features

Elastic Modulus Comparison (GPa)

Elastic Features

Elastic Anisotropy A^U

0.0400

Homogeneous Poisson ν

0.2050

Debye Temperature

928.2

Sound Velocity

6,385.7

m/s

Homogeneity

0.2050

Related Tasks

Related computation task IDs (5)

aaadmopn aaadswek aaaemhnr aaaeubuh aaafcryu

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-637575

Reference Citation

The crystal structure and related material properties of AlCr3B4 were obtained from the Materials Project database (MP-ID: mp-637575, 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…

Style: Ball & Stick | Drag to rotate · Scroll to zoom · Right-click to pan

Raw CIF Data

# generated using pymatgen
data_AlCr3B4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.92092274
_cell_length_b   2.91841184
_cell_length_c   8.05827478
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   90.00000000
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AlCr3B4
_chemical_formula_sum   'Al1 Cr3 B4'
_cell_volume   68.69240483
_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
  Al  Al0  1  0.50000000  0.50000000  0.50000000  1.0
  Cr  Cr1  1  0.00000000  -0.00000000  0.70200793  1.0
  Cr  Cr2  1  -0.00000000  0.00000000  0.29799207  1.0
  Cr  Cr3  1  0.00000000  0.50000000  -0.00000000  1.0
  B  B4  1  0.50000000  0.00000000  0.10800941  1.0
  B  B5  1  0.50000000  0.50000000  0.22379044  1.0
  B  B6  1  0.50000000  0.00000000  0.89199059  1.0
  B  B7  1  0.50000000  0.50000000  0.77620956  1.0

Get direct link