Ta16Nb8SiP7

High-Entropy Materials HEA

MP-ID: mp-3292301 · Space group: P2 (#3)

Materials Project API

Basic Information

Formula

Ta16Nb8SiP7

MP-ID

mp-3292301

Elements

Sites

Density

12.2128

g/cm³

Volume

528.01

Å³

Cell a

10.1880

Cell b

10.2609

Cell c

5.0509

α Angle

90.00

β Angle

90.17

γ Angle

90.00

Space Group

Point Group

Crystal System

Monoclinic

Bravais Lattice

Stability

Yes

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
12.24	7.2296	100.0	(1,1,0)
17.28	5.1305	5.1	(0,2,0)
17.41	5.0940	5.8	(2,0,0)
24.63	3.6148	33.4	(2,2,0)
24.74	3.5993	3.7	(0,2,1)
24.79	3.5921	1.8	(2,0,-1)
24.86	3.5812	2.2	(2,0,1)
27.51	3.2425	6.5	(1,3,0)
27.67	3.2240	6.4	(3,1,0)
32.81	2.7298	6.1	(1,3,-1)
32.84	2.7274	7.0	(1,3,1)
32.92	2.7211	6.9	(3,1,-1)
33.00	2.7140	6.1	(3,1,1)
34.98	2.5652	1.2	(0,4,0)
35.55	2.5254	40.7	(0,0,2)
36.27	2.4770	71.0	(2,3,-1)
36.32	2.4735	70.5	(2,3,1)
36.33	2.4727	72.1	(3,2,-1)
36.41	2.4674	73.4	(3,2,1)
37.31	2.4099	71.3	(3,3,0)
37.71	2.3858	56.6	(1,1,-2)
37.76	2.3826	55.3	(1,1,2)
39.33	2.2911	26.7	(2,4,0)
39.40	2.2872	7.7	(0,4,1)

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Energy Properties

Formation Energy/atom

-0.65342

eV/atom

Energy/atom

-33.37624

eV/atom

Energy above Hull

0.0000

eV/atom

Uncorrected Energy

-33.3762

eV/atom

Volume/atom

16.50

Å³

c/a Ratio

0.4958

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Total Mag. Moment

0.0013

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.000000

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

Ta · 0.500

Element Family

5d-TM

Solute Fraction

0.500

Interstitial Fraction

0.250

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

1.1339

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

9.4274

J/mol·K

Ω Parameter

1.1050

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

11.116%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.2759

smaller = more stable mixing

VEC

4.969

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-20.941

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8179

SS Former

Phase Tendency

Related Tasks

Related computation task IDs (1)

aaahfigz

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-3292301

Reference Citation

The crystal structure and related material properties of Ta16Nb8SiP7 were obtained from the Materials Project database (MP-ID: mp-3292301, 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_Ta16Nb8SiP7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.18797358
_cell_length_b   10.26092048
_cell_length_c   5.05086691
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.17350507
_cell_angle_gamma   90.00000000
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ta16Nb8SiP7
_chemical_formula_sum   'Ta16 Nb8 Si1 P7'
_cell_volume   528.00503716
_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
  Ta  Ta0  1  0.90814385  0.59065140  0.49919619  1.0
  Ta  Ta1  1  0.90666955  0.40662056  0.00008789  1.0
  Ta  Ta2  1  0.59201679  0.09225458  0.50089253  1.0
  Ta  Ta3  1  0.79925046  0.30006111  0.50044738  1.0
  Ta  Ta4  1  0.09333045  0.40662056  0.49991211  1.0
  Ta  Ta5  1  0.09185615  0.59065140  0.00080381  1.0
  Ta  Ta6  1  0.20074954  0.30006111  0.99955262  1.0
  Ta  Ta7  1  0.29682512  0.80029192  0.99543152  1.0
  Ta  Ta8  1  0.30078793  0.20017342  0.49843096  1.0
  Ta  Ta9  1  0.69921207  0.20017342  0.00156904  1.0
  Ta  Ta10  1  0.59226922  0.90681922  0.00128047  1.0
  Ta  Ta11  1  0.70317488  0.80029192  0.50456848  1.0
  Ta  Ta12  1  0.20101127  0.69854865  0.49799119  1.0
  Ta  Ta13  1  0.40798321  0.09225458  0.99910747  1.0
  Ta  Ta14  1  0.40773078  0.90681922  0.49871953  1.0
  Ta  Ta15  1  0.79898873  0.69854865  0.00200881  1.0
  Nb  Nb16  1  0.50000000  0.64537784  0.25000000  1.0
  Nb  Nb17  1  0.85292144  0.00367396  0.75081852  1.0
  Nb  Nb18  1  0.64551228  0.49943514  0.74957511  1.0
  Nb  Nb19  1  0.00000000  0.85535028  0.25000000  1.0
  Nb  Nb20  1  0.35448772  0.49943514  0.75042489  1.0
  Nb  Nb21  1  0.00000000  0.14699281  0.25000000  1.0
  Nb  Nb22  1  0.50000000  0.35336021  0.25000000  1.0
  Nb  Nb23  1  0.14707856  0.00367396  0.74918148  1.0
  Si  Si24  1  0.00000000  0.79429896  0.75000000  1.0
  P  P25  1  0.50000000  0.29138507  0.75000000  1.0
  P  P26  1  0.20841477  0.00033447  0.24953273  1.0
  P  P27  1  0.79158523  0.00033447  0.25046727  1.0
  P  P28  1  0.00000000  0.20914766  0.75000000  1.0
  P  P29  1  0.70786294  0.49896889  0.24994792  1.0
  P  P30  1  0.29213706  0.49896889  0.25005208  1.0
  P  P31  1  0.50000000  0.70842252  0.75000000  1.0

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