Na2Cr7O14

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-754789 · Space group: R-3m (#166)

Materials Project API

Basic Information

Formula

Na2Cr7O14

MP-ID

mp-754789

Elements

Sites

Density

3.9136

g/cm³

Volume

268.98

Å³

Cell a

9.9483

Cell b

9.9483

Cell c

9.9483

α Angle

33.63

β Angle

33.63

γ Angle

33.63

Space Group

R-3m

Point Group

-3m

Crystal System

Trigonal

Bravais Lattice

Stability

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
9.43	9.3770	100.0	(1,1,1)
18.08	4.9077	9.3	(1,0,0)
18.89	4.6979	6.0	(1,1,0)
18.89	4.6979	12.0	(1,0,1)
21.86	4.0665	8.0	(1,1,2)
21.86	4.0665	16.0	(2,1,1)
23.85	3.7308	14.8	(2,2,1)
28.53	3.1285	4.7	(3,2,2)
28.56	3.1257	27.2	(3,3,3)
31.08	2.8776	20.2	(1,0,-1)
31.08	2.8776	10.1	(1,-1,0)
31.13	2.8733	24.1	(3,3,2)
31.13	2.8733	48.2	(3,2,3)
32.55	2.7510	18.5	(2,1,0)
36.19	2.4824	2.2	(1,1,-1)
36.19	2.4824	4.5	(1,-1,1)
36.62	2.4539	16.5	(2,0,0)
36.64	2.4525	49.5	(3,2,1)
36.68	2.4498	4.8	(4,3,3)
38.32	2.3490	1.0	(2,2,0)
38.32	2.3490	2.1	(2,0,2)
39.55	2.2786	51.6	(3,1,1)
39.61	2.2753	1.4	(4,4,3)
39.61	2.2753	2.9	(4,3,4)

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Energy Properties

Formation Energy/atom

-2.05403

eV/atom

Energy/atom

-8.12039

eV/atom

Energy above Hull

0.1145

eV/atom

Uncorrected Energy

-7.0938

eV/atom

Volume/atom

11.69

Å³

c/a Ratio

1.0000

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Yes

Total Mag. Moment

4.0000

μB

Mag. Ordering

FiM

Mag. Sites

Magnetization/Volume

0.014870

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

O · 0.609

Element Family

Metalloid-Nonmetal

Solute Fraction

0.391

Interstitial Fraction

0.000

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

0.8766

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

7.2881

J/mol·K

Ω Parameter

3.7121

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

46.110%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.9667

smaller = more stable mixing

VEC

4.348

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

1.431

kJ/mol; negative = exothermic mixing

Entropy Norm

0.7979

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.508

Family

O-rich Multi-Component

Matrix Element

O · 0.609

Related Tasks

Related computation task IDs (2)

aaabznke aaadwrfl

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-754789

Reference Citation

The crystal structure and related material properties of Na2Cr7O14 were obtained from the Materials Project database (MP-ID: mp-754789, 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_Na2Cr7O14
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.94833524
_cell_length_b   9.94833524
_cell_length_c   9.94833480
_cell_angle_alpha   33.62678936
_cell_angle_beta   33.62678936
_cell_angle_gamma   33.62678211
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2Cr7O14
_chemical_formula_sum   'Na2 Cr7 O14'
_cell_volume   268.97985424
_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
  Na  Na0  1  0.30170700  0.30170700  0.30170700  1.0
  Na  Na1  1  0.69829300  0.69829300  0.69829300  1.0
  Cr  Cr2  1  0.50000000  0.00000000  0.00000000  1.0
  Cr  Cr3  1  0.06041200  0.06041200  0.06041200  1.0
  Cr  Cr4  1  0.00000000  0.00000000  0.50000000  1.0
  Cr  Cr5  1  0.00000000  0.50000000  0.00000000  1.0
  Cr  Cr6  1  0.57608600  0.57608600  0.57608600  1.0
  Cr  Cr7  1  0.42391400  0.42391400  0.42391400  1.0
  Cr  Cr8  1  0.93958800  0.93958800  0.93958800  1.0
  O  O9  1  0.12853600  0.12853600  0.12853600  1.0
  O  O10  1  0.63706000  0.11643100  0.63706000  1.0
  O  O11  1  0.88356900  0.36294000  0.36294000  1.0
  O  O12  1  0.77809900  0.29906000  0.77809900  1.0
  O  O13  1  0.70094000  0.22190100  0.22190100  1.0
  O  O14  1  0.22190100  0.22190100  0.70094000  1.0
  O  O15  1  0.36294000  0.36294000  0.88356900  1.0
  O  O16  1  0.63706000  0.63706000  0.11643100  1.0
  O  O17  1  0.77809900  0.77809900  0.29906000  1.0
  O  O18  1  0.29906000  0.77809900  0.77809900  1.0
  O  O19  1  0.22190100  0.70094000  0.22190100  1.0
  O  O20  1  0.11643100  0.63706000  0.63706000  1.0
  O  O21  1  0.36294000  0.88356900  0.36294000  1.0
  O  O22  1  0.87146400  0.87146400  0.87146400  1.0

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