BiP2O7

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-672981 · Space group: P2_1/c (#14)

Materials Project API

Basic Information

Formula

BiP2O7

MP-ID

mp-672981

Elements

Sites

Density

3.9305

g/cm³

Volume

647.10

Å³

Cell a

5.4677

Cell b

9.3332

Cell c

14.1635

α Angle

63.55

β Angle

90.00

γ Angle

90.00

Space Group

P2_1/c

Point Group

2/m

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
10.59	8.3561	1.4	(0,1,0)
13.25	6.6843	4.5	(0,1,2)
13.97	6.3403	68.3	(0,0,2)
19.40	4.5752	20.3	(1,1,0)
19.56	4.5393	12.8	(0,2,2)
20.99	4.2321	100.0	(1,1,2)
21.03	4.2253	6.2	(0,1,-2)
21.27	4.1780	59.3	(0,2,0)
21.46	4.1407	7.6	(1,0,2)
25.22	3.5313	3.3	(0,1,4)
25.50	3.4925	3.3	(1,2,2)
26.66	3.3433	18.4	(1,1,-2)
26.67	3.3421	6.5	(0,2,4)
26.86	3.3198	2.0	(1,2,0)
27.68	3.2231	1.1	(1,2,3)
28.15	3.1702	1.5	(0,0,4)
30.13	2.9664	29.9	(1,1,4)
30.42	2.9387	13.4	(0,2,-2)
31.37	2.8516	7.7	(1,2,4)
31.96	2.8005	1.4	(0,3,4)
32.14	2.7854	1.2	(0,3,0)
32.65	2.7425	10.7	(1,0,4)
32.76	2.7338	16.9	(2,0,0)
33.13	2.7039	24.0	(1,3,2)

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Energy Properties

Formation Energy/atom

-2.29619

eV/atom

Energy/atom

-7.23186

eV/atom

Energy above Hull

0.0526

eV/atom

Uncorrected Energy

-6.7510

eV/atom

Volume/atom

16.18

Å³

c/a Ratio

2.5904

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Total Mag. Moment

3.9811

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.006150

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

O · 0.700

Element Family

Metalloid-Nonmetal

Solute Fraction

0.300

Interstitial Fraction

0.200

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

0.8018

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

6.6663

J/mol·K

Ω Parameter

0.4942

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

41.458%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.6004

smaller = more stable mixing

VEC

4.300

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-2.108

kJ/mol; negative = exothermic mixing

Entropy Norm

0.7298

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.624

Family

Interstitial Alloy

Matrix Element

O · 0.700

Related Tasks

Related computation task IDs (2)

aaabqpou aaaednfv

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-672981

Reference Citation

The crystal structure and related material properties of BiP2O7 were obtained from the Materials Project database (MP-ID: mp-672981, 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_BiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.46764900
_cell_length_b   9.33317800
_cell_length_c   14.16350118
_cell_angle_alpha   63.54780171
_cell_angle_beta   90.00000000
_cell_angle_gamma   90.00000000
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BiP2O7
_chemical_formula_sum   'Bi4 P8 O28'
_cell_volume   647.10155695
_cell_formula_units_Z   4
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
  Bi  Bi0  1  0.73600800  0.73620400  0.52734200  1.0
  Bi  Bi1  1  0.76399200  0.73620400  0.02734200  1.0
  Bi  Bi2  1  0.23600800  0.26379600  0.97265800  1.0
  Bi  Bi3  1  0.26399200  0.26379600  0.47265800  1.0
  P  P4  1  0.75115900  0.18086900  0.34989700  1.0
  P  P5  1  0.74884100  0.18086900  0.84989700  1.0
  P  P6  1  0.27477800  0.68774000  0.88257500  1.0
  P  P7  1  0.72522200  0.31226000  0.11742500  1.0
  P  P8  1  0.22522200  0.68774000  0.38257500  1.0
  P  P9  1  0.77477800  0.31226000  0.61742500  1.0
  P  P10  1  0.24884100  0.81913100  0.65010300  1.0
  P  P11  1  0.25115900  0.81913100  0.15010300  1.0
  O  O12  1  0.63890200  0.24968600  0.54857600  1.0
  O  O13  1  0.27548600  0.99098800  0.06619000  1.0
  O  O14  1  0.22451400  0.99098800  0.56619000  1.0
  O  O15  1  0.86109800  0.24968600  0.04857600  1.0
  O  O16  1  0.94939400  0.68167100  0.40455400  1.0
  O  O17  1  0.67441700  0.46846400  0.61238000  1.0
  O  O18  1  0.72451400  0.00901200  0.93381000  1.0
  O  O19  1  0.50227200  0.74381800  0.65563000  1.0
  O  O20  1  0.32558300  0.53153600  0.38762000  1.0
  O  O21  1  0.77548600  0.00901200  0.43381000  1.0
  O  O22  1  0.95941600  0.28752300  0.35597800  1.0
  O  O23  1  0.44939400  0.31832900  0.09544600  1.0
  O  O24  1  0.99772800  0.74381800  0.15563000  1.0
  O  O25  1  0.54058400  0.28752300  0.85597800  1.0
  O  O26  1  0.45941600  0.71247700  0.14402200  1.0
  O  O27  1  0.22533900  0.82323300  0.76305200  1.0
  O  O28  1  0.04058400  0.71247700  0.64402200  1.0
  O  O29  1  0.72533900  0.17676700  0.73694800  1.0
  O  O30  1  0.17441700  0.53153600  0.88762000  1.0
  O  O31  1  0.49772800  0.25618200  0.34437000  1.0
  O  O32  1  0.82558300  0.46846400  0.11238000  1.0
  O  O33  1  0.27466100  0.82323300  0.26305200  1.0
  O  O34  1  0.36109800  0.75031400  0.45142400  1.0
  O  O35  1  0.00227200  0.25618200  0.84437000  1.0
  O  O36  1  0.05060600  0.31832900  0.59544600  1.0
  O  O37  1  0.77466100  0.17676700  0.23694800  1.0
  O  O38  1  0.55060600  0.68167100  0.90455400  1.0
  O  O39  1  0.13890200  0.75031400  0.95142400  1.0

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