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NpUB8

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-3297642 · Space group: Pmc2_1 (#26)

Basic Information

Formula
NpUB8
MP-ID
mp-3297642
Elements
3
Sites
20
Density
9.2257
g/cm³
Volume
202.14
ų
Cell a
7.1024
Å
Cell b
7.0904
Å
Cell c
4.0139
Å
α Angle
90.00
°
β Angle
90.00
°
γ Angle
90.00
°
Space Group
Pmc2_1
Point Group
mm2
Crystal System
Orthorhombic
Bravais Lattice
Orthorhombic P
Stability
Yes
Packing Fraction
0.5240

X-ray Diffraction

Diffraction Pattern
X-axis: 2θ (°); Y-axis: relative intensity; CuKa ; λ=1.5406 Å
Diffraction Peaks (Top 24)
2θd (Å)Ihkl
17.68 5.0179 3.6 (1,1,0)
22.15 4.0139 100.0 (0,0,1)
25.08 3.5512 38.7 (2,0,0)
25.12 3.5452 39.1 (0,2,0)
28.10 3.1752 56.6 (2,1,0)
28.13 3.1720 55.5 (1,2,0)
28.48 3.1345 5.3 (1,1,1)
33.70 2.6597 47.6 (2,0,1)
33.73 2.6572 48.2 (0,2,1)
35.79 2.5090 20.1 (2,2,0)
36.07 2.4903 69.9 (2,1,1)
36.09 2.4887 68.5 (1,2,1)
40.16 2.2456 7.6 (3,1,0)
40.21 2.2426 7.6 (1,3,0)
42.49 2.1275 28.8 (2,2,1)
45.18 2.0070 23.4 (0,0,2)
46.10 1.9688 3.0 (3,2,0)
46.14 1.9675 3.2 (2,3,0)
46.33 1.9598 10.8 (3,1,1)
46.38 1.9577 10.9 (1,3,1)
48.88 1.8634 1.8 (1,1,2)
51.71 1.7676 3.8 (3,2,1)
51.74 1.7667 4.1 (2,3,1)
52.36 1.7472 13.6 (2,0,2)
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Energy Properties

Formation Energy/atom
-0.55352
eV/atom
Energy/atom
-22.72723
eV/atom
Energy above Hull
0.0000
eV/atom
Uncorrected Energy
-22.7272
eV/atom
Volume/atom
10.11
ų
c/a Ratio
-

Electronic Properties

Metallic
Metal
Band Gap
0
eV
Direct Gap
No
CBM
N/A
eV

Magnetic Properties

Magnetic
Yes
Total Mag. Moment
7.1333
μB
Mag. Ordering
FM
Mag. Sites
4
Magnetization/Volume
0.035290
μB/ų

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)
Composition Info
Major / Matrix Element
B · 0.800
Element Family
Metalloid-Nonmetal
Solute Fraction
0.200
Interstitial Fraction
0.800

High-Entropy Alloy Features

Composite Radar (normalized)
Element-Class Share
Mix Entropy ΔS/R
0.6390
HEA criterion (>1.0 = high entropy)
Mix Entropy ΔS
5.3129
J/mol·K
Ω Parameter
0.0000
Ω > 1.1 favors solid solution
Atomic Size Mismatch δr
31.776%
δr < 6.6% favors single-phase solid solution
Electronegativity Diff Δχ
0.2680
smaller = more stable mixing
VEC
3.000
valence electron concentration, affects phase stability
Mix Enthalpy ΔH_mix
0.000
kJ/mol; negative = exothermic mixing
Entropy Norm
0.5817
SS Former
0
Phase Tendency
IM

Traditional Material Features

ROM Blended-Feature Radar
Rating & Classification
Tier
B
Score
0.598
Family
Interstitial Alloy
Matrix Element
B · 0.800

Related Tasks

Related computation task IDs (1)

Citation & References

Materials Project Page
https://materialsproject.org/materials/mp-3297642
Reference Citation

The crystal structure and related material properties of NpUB8 were obtained from the Materials Project database (MP-ID: mp-3297642, 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

BibTeX
@article{Horton2025,
  author  = {Horton, Matthew K. and Huck, Patrick and Yang, Ruo Xi and Munro, Jason M. and Dwaraknath, Shyam and Ganose, Alex M. and Kingsbury, Ryan S. and Wen, Mingjian and Shen, Jimmy X. and Mathis, Tyler S. and Kaplan, Aaron D. and Berket, Karlo and Riebesell, Janosh and George, Janine and Rosen, Andrew S. and Spotte-Smith, Evan W. C. and McDermott, Matthew J. and Cohen, Orion A. and Dunn, Alex and Kuner, Matthew C. and Rignanese, Gian-Marco and Petretto, Guido and Waroquiers, David and Griffin, Sinead M. and Neaton, Jeffrey B. and Chrzan, Daryl C. and Asta, Mark and Hautier, Geoffroy and Cholia, Shreyas and Ceder, Gerbrand and Ong, Shyue Ping and Jain, Anubhav and Persson, Kristin A.},
  title   = {Accelerated data-driven materials science with the Materials Project},
  journal = {Nature Materials},
  year    = {2025},
  volume  = {24},
  number  = {10},
  pages   = {1522--1532},
  month   = {oct},
  doi     = {10.1038/s41563-025-02272-0},
  issn    = {1476-4660},
  url     = {https://doi.org/10.1038/s41563-025-02272-0},
  abstract = {The Materials Project was launched formally in 2011 to drive materials discovery forwards through high-throughput computation and open data. More than a decade later, the Materials Project has become an indispensable tool used by more than 600,000 materials researchers around the world. This Perspective describes how the Materials Project, as a data platform and a software ecosystem, has helped to shape research in data-driven materials science. We cover how sustainable software and computational methods have accelerated materials design while becoming more open source and collaborative in nature. Next, we present cases where the Materials Project was used to understand and discover functional materials. We then describe our efforts to meet the needs of an expanding user base, through technical infrastructure updates ranging from data architecture and cloud resources to interactive web applications. Finally, we discuss opportunities to better aid the research community, with the vision that more accessible and easy-to-understand materials data will result in democratized materials knowledge and an increasingly collaborative community.}
}

3D Crystal Structure Rendering

Loading 3D structure…

Style: Ball & Stick
Raw CIF Data
# generated using pymatgen
data_NpUB8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.10241710
_cell_length_b   7.09036855
_cell_length_c   4.01392917
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   90.00000000
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NpUB8
_chemical_formula_sum   'Np2 U2 B16'
_cell_volume   202.13647478
_cell_formula_units_Z   2
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
  Np  Np0  1  0.81294303  0.31205623  0.00000000  1.0
  Np  Np1  1  0.31294303  0.18794377  0.00000000  1.0
  U  U2  1  0.68818582  0.81156571  0.00000000  1.0
  U  U3  1  0.18818582  0.68843429  0.00000000  1.0
  B  B4  1  0.99975561  0.00092280  0.20050929  1.0
  B  B5  1  0.49975561  0.49907720  0.79949071  1.0
  B  B6  1  0.99975561  0.00092280  0.79949071  1.0
  B  B7  1  0.49975561  0.49907720  0.20050929  1.0
  B  B8  1  0.58809266  0.08557386  0.50000000  1.0
  B  B9  1  0.08809266  0.41442614  0.50000000  1.0
  B  B10  1  0.91071847  0.58737883  0.50000000  1.0
  B  B11  1  0.41071847  0.91262117  0.50000000  1.0
  B  B12  1  0.03858102  0.17847364  0.50000000  1.0
  B  B13  1  0.17710770  0.96366628  0.50000000  1.0
  B  B14  1  0.82302738  0.03840926  0.50000000  1.0
  B  B15  1  0.96183170  0.82314529  0.50000000  1.0
  B  B16  1  0.46183170  0.67685471  0.50000000  1.0
  B  B17  1  0.53858102  0.32152636  0.50000000  1.0
  B  B18  1  0.67710770  0.53633372  0.50000000  1.0
  B  B19  1  0.32302738  0.46159074  0.50000000  1.0
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