Ba2Ni3O7
High-Entropy Materials HEA Traditional Materials TRAMP-ID: mp-1048554 · Space group: Pmmm (#47)
Basic Information
Formula
Ba2Ni3O7
MP-ID
mp-1048554
Elements
3
Sites
12
Density
5.1709
g/cm³
Volume
180.71
ų
Cell a
3.7073
Å
Cell b
3.7364
Å
Cell c
13.0458
Å
α Angle
90.00
°
β Angle
90.00
°
γ Angle
90.00
°
Space Group
Pmmm
Point Group
mmm
Crystal System
Orthorhombic
Bravais Lattice
oP
Stability
No
Packing Fraction
-
X-ray Diffraction
Diffraction Pattern
X-axis: 2θ (°); Y-axis: relative intensity; Cu Kα ; λ=1.5418 Å
Diffraction Peaks (Top 24)
| 2θ | d (Å) | I | hkl |
|---|---|---|---|
| 6.78 | 13.0458 | 30.3 | (0,0,1) |
| 13.57 | 6.5229 | 47.7 | (0,0,2) |
| 23.81 | 3.7364 | 1.6 | (0,1,0) |
| 24.79 | 3.5920 | 17.2 | (0,1,1) |
| 24.97 | 3.5661 | 7.7 | (1,0,1) |
| 27.35 | 3.2615 | 3.4 | (0,0,4) |
| 27.51 | 3.2422 | 72.5 | (0,1,2) |
| 27.68 | 3.2231 | 91.1 | (1,0,2) |
| 31.57 | 2.8340 | 73.9 | (0,1,3) |
| 31.72 | 2.8212 | 90.2 | (1,0,3) |
| 34.07 | 2.6317 | 100.0 | (1,1,0) |
| 34.37 | 2.6092 | 62.1 | (0,0,5) |
| 34.78 | 2.5797 | 11.6 | (1,1,1) |
| 36.57 | 2.4571 | 15.0 | (0,1,4) |
| 36.70 | 2.4487 | 9.6 | (1,0,4) |
| 36.83 | 2.4406 | 18.1 | (1,1,2) |
| 40.05 | 2.2515 | 24.3 | (1,1,3) |
| 41.53 | 2.1743 | 7.1 | (0,0,6) |
| 42.25 | 2.1392 | 4.0 | (0,1,5) |
| 42.36 | 2.1337 | 2.2 | (1,0,5) |
| 48.44 | 1.8793 | 1.5 | (0,1,6) |
| 48.74 | 1.8682 | 33.6 | (0,2,0) |
| 48.87 | 1.8637 | 4.2 | (0,0,7) |
| 49.15 | 1.8537 | 32.7 | (2,0,0) |
Energy Properties
Formation Energy/atom
-1.28875
eV/atom
Energy/atom
-5.93992
eV/atom
Energy above Hull
0.4310
eV/atom
Uncorrected Energy
-4.9039
eV/atom
Volume/atom
15.06
ų
c/a Ratio
3.5189
Electronic Properties
Metallic
Metal
Band Gap
0
eV
Direct Gap
No
CBM
N/A
eV
Magnetic Properties
Magnetic
Yes
Total Mag. Moment
5.0160
μB
Mag. Ordering
FM
Mag. Sites
3
Magnetization/Volume
0.027760
μB/ų
Elastic Properties
Elastic data not available
Feature Analysis
Composition Overview
Element Composition (atomic fraction)
Composition Info
Major / Matrix Element
O · 0.583
Element Family
Metalloid-Nonmetal
Solute Fraction
0.417
Interstitial Fraction
0.000
High-Entropy Alloy Features
Composite Radar (normalized)
Element-Class Share
Mix Entropy ΔS/R
0.9596
HEA criterion (>1.0 = high entropy)
Mix Entropy ΔS
7.9782
J/mol·K
Ω Parameter
0.0000
Ω > 1.1 favors solid solution
Atomic Size Mismatch δr
56.224%
δr < 6.6% favors single-phase solid solution
Electronegativity Diff Δχ
1.0084
smaller = more stable mixing
VEC
5.167
valence electron concentration, affects phase stability
Mix Enthalpy ΔH_mix
0.000
kJ/mol; negative = exothermic mixing
Entropy Norm
0.8735
SS Former
0
Phase Tendency
IM
Traditional Material Features
ROM Blended-Feature Radar
Rating & Classification
Tier
C
Score
0.333
Family
O-rich Multi-Component
Matrix Element
O · 0.583
Related Tasks
Citation & References
Materials Project Page
https://materialsproject.org/materials/mp-1048554
Reference Citation
The crystal structure and related material properties of Ba2Ni3O7 were obtained from the Materials Project database (MP-ID: mp-1048554, 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_Ba2Ni3O7
_symmetry_space_group_name_H-M 'P 1'
_cell_length_a 3.70732600
_cell_length_b 3.73639800
_cell_length_c 13.04578300
_cell_angle_alpha 90.00000000
_cell_angle_beta 90.00000000
_cell_angle_gamma 90.00000000
_symmetry_Int_Tables_number 1
_chemical_formula_structural Ba2Ni3O7
_chemical_formula_sum 'Ba2 Ni3 O7'
_cell_volume 180.71077907
_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
Ba Ba0 1 0.50000000 0.50000000 0.80282000 1.0
Ba Ba1 1 0.50000000 0.50000000 0.19718000 1.0
Ni Ni2 1 0.00000000 0.00000000 0.61726600 1.0
Ni Ni3 1 0.00000000 0.00000000 0.38273400 1.0
Ni Ni4 1 0.00000000 0.00000000 0.00000000 1.0
O O5 1 0.00000000 0.50000000 0.00000000 1.0
O O6 1 0.50000000 0.00000000 0.64120000 1.0
O O7 1 0.50000000 0.00000000 0.35880000 1.0
O O8 1 0.00000000 0.50000000 0.64273500 1.0
O O9 1 0.00000000 0.50000000 0.35726500 1.0
O O10 1 0.00000000 0.00000000 0.86158500 1.0
O O11 1 0.00000000 0.00000000 0.13841500 1.0
