H4N2O3

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-625635 · Space group: C2 (#5)

Materials Project API

Basic Information

Formula

H4N2O3

MP-ID

mp-625635

Elements

Sites

Density

1.2121

g/cm³

Volume

109.66

Å³

Cell a

4.7273

Cell b

4.7273

Cell c

4.9578

α Angle

88.61

β Angle

88.61

γ Angle

97.94

Space Group

Point Group

Crystal System

Monoclinic

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
17.90	4.9544	4.6	(0,0,1)
18.96	4.6802	25.8	(1,0,0)
24.97	3.5661	4.8	(1,-1,0)
25.82	3.4506	58.0	(1,0,1)
26.56	3.3558	28.1	(1,0,-1)
28.79	3.1011	8.1	(1,1,0)
30.90	2.8943	100.0	(1,-1,1)
33.52	2.6735	9.7	(1,1,1)
34.69	2.5860	11.6	(1,1,-1)
36.26	2.4772	34.2	(0,0,2)
38.47	2.3401	13.6	(2,0,0)
40.64	2.2199	14.4	(2,-1,0)
40.73	2.2151	7.0	(1,0,2)
41.73	2.1646	1.3	(1,0,-2)
42.25	2.1391	3.5	(2,0,1)
43.21	2.0935	2.1	(2,0,-1)
44.53	2.0345	1.0	(1,-1,2)
44.97	2.0159	1.1	(2,-1,-1)
45.69	1.9857	4.7	(2,1,0)
46.04	1.9714	2.8	(1,1,2)
51.23	1.7831	3.7	(2,-2,0)
53.08	1.7253	2.2	(2,0,2)
54.70	1.6779	4.9	(2,0,-2)
55.19	1.6642	6.1	(2,-1,2)

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Energy Properties

Formation Energy/atom

-0.29129

eV/atom

Energy/atom

-5.30252

eV/atom

Energy above Hull

0.6808

eV/atom

Uncorrected Energy

-5.0735

eV/atom

Volume/atom

12.18

Å³

c/a Ratio

1.0488

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Total Mag. Moment

0.0095

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.000090

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

H · 0.444

Element Family

Alkali-AlkEarth

Solute Fraction

0.556

Interstitial Fraction

0.222

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.0609

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

8.8200

J/mol·K

Ω Parameter

0.0000

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

44.155%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.5562

smaller = more stable mixing

VEC

2.889

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

0.000

kJ/mol; negative = exothermic mixing

Entropy Norm

0.9656

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.234

Family

H-rich Multi-Component

Matrix Element

H · 0.444

Related Tasks

Related computation task IDs (5)

aaadeexs aaadohxh aaadumlx aaaeqfnu aaafbass

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-625635

Reference Citation

The crystal structure and related material properties of H4N2O3 were obtained from the Materials Project database (MP-ID: mp-625635, 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_H4N2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.72729327
_cell_length_b   4.72729327
_cell_length_c   4.95782585
_cell_angle_alpha   88.60964824
_cell_angle_beta   88.60964824
_cell_angle_gamma   97.94054842
_symmetry_Int_Tables_number   1
_chemical_formula_structural   H4N2O3
_chemical_formula_sum   'H4 N2 O3'
_cell_volume   109.65674713
_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
  H  H0  1  0.63875400  0.61135800  0.97955800  1.0
  H  H1  1  0.38864200  0.36124600  0.02044200  1.0
  H  H2  1  0.06079200  0.84315900  0.15309500  1.0
  H  H3  1  0.15684100  0.93920800  0.84690500  1.0
  N  N4  1  0.01687400  0.98312600  0.00000000  1.0
  N  N5  1  0.67037700  0.32962300  0.50000000  1.0
  O  O6  1  0.43143600  0.56856400  0.00000000  1.0
  O  O7  1  0.91683700  0.44126000  0.47224400  1.0
  O  O8  1  0.55874000  0.08316300  0.52775600  1.0

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