Basic Information
Formula
Rb2CoSe2
MP-ID
mp-8769
Elements
3
Sites
10
Density
3.9489
g/cm³
Volume
326.14
ų
Cell a
8.4411
Å
Cell b
8.4411
Å
Cell c
8.4411
Å
α Angle
134.35
°
β Angle
129.30
°
γ Angle
70.58
°
Space Group
Ibam
Point Group
mmm
Crystal System
Orthorhombic
Bravais Lattice
oI
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 |
|---|---|---|---|
| 12.85 | 6.8898 | 28.1 | (1,1,-1) |
| 13.84 | 6.4009 | 46.3 | (1,0,0) |
| 22.41 | 3.9677 | 1.3 | (1,1,0) |
| 22.94 | 3.8767 | 36.2 | (2,1,-1) |
| 24.63 | 3.6140 | 16.9 | (1,-1,1) |
| 25.86 | 3.4449 | 41.3 | (2,2,-2) |
| 27.23 | 3.2745 | 60.5 | (1,-1,-1) |
| 27.88 | 3.2004 | 4.8 | (2,0,0) |
| 28.95 | 3.0839 | 100.0 | (1,0,1) |
| 30.22 | 2.9575 | 3.2 | (0,2,0) |
| 30.67 | 2.9152 | 6.4 | (0,1,1) |
| 31.86 | 2.8091 | 61.5 | (2,2,-1) |
| 34.42 | 2.6057 | 59.6 | (2,1,0) |
| 36.02 | 2.4936 | 36.5 | (3,1,-1) |
| 37.05 | 2.4266 | 45.4 | (0,0,2) |
| 37.91 | 2.3734 | 75.4 | (1,3,-1) |
| 39.37 | 2.2888 | 5.9 | (1,1,1) |
| 42.36 | 2.1336 | 1.6 | (3,0,0) |
| 43.55 | 2.0782 | 14.6 | (3,2,-1) |
| 43.60 | 2.0759 | 1.7 | (3,3,-2) |
| 44.77 | 2.0242 | 12.7 | (2,3,-1) |
| 45.74 | 1.9838 | 6.6 | (2,2,0) |
| 46.87 | 1.9383 | 2.0 | (4,2,-2) |
| 47.30 | 1.9217 | 5.3 | (1,0,2) |
Energy Properties
Formation Energy/atom
-0.90180
eV/atom
Energy/atom
-4.11906
eV/atom
Energy above Hull
0.0296
eV/atom
Uncorrected Energy
-3.9303
eV/atom
Volume/atom
32.61
ų
c/a Ratio
1.0000
Electronic Properties
Metallic
Metal
Band Gap
0
eV
Direct Gap
No
CBM
N/A
eV
Magnetic Properties
Magnetic
Yes
Total Mag. Moment
5.9996
μB
Mag. Ordering
FM
Mag. Sites
2
Magnetization/Volume
0.018400
μB/ų
Elastic Properties
Elastic data not available
Feature Analysis
Element Composition (atomic fraction)
Composition Info
Major / Matrix Element
Rb · 0.400
Element Family
Alkali-AlkEarth
Solute Fraction
0.600
Interstitial Fraction
0.000
Composite Radar (normalized)
Element-Class Share
Mix Entropy ΔS/R
1.0549
HEA criterion (>1.0 = high entropy)
Mix Entropy ΔS
8.7706
J/mol·K
Ω Parameter
0.0000
Ω > 1.1 favors solid solution
Atomic Size Mismatch δr
34.710%
δr < 6.6% favors single-phase solid solution
Electronegativity Diff Δχ
0.7776
smaller = more stable mixing
VEC
3.800
valence electron concentration, affects phase stability
Mix Enthalpy ΔH_mix
0.000
kJ/mol; negative = exothermic mixing
Entropy Norm
0.9602
SS Former
0
Phase Tendency
IM
Related Tasks
Citation & References
Materials Project Page
https://materialsproject.org/materials/mp-8769
Reference Citation
The crystal structure and related material properties of Rb2CoSe2 were obtained from the Materials Project database (MP-ID: mp-8769, 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_Rb2CoSe2
_symmetry_space_group_name_H-M 'P 1'
_cell_length_a 8.44111098
_cell_length_b 8.44111098
_cell_length_c 8.44111098
_cell_angle_alpha 134.34958911
_cell_angle_beta 129.30033778
_cell_angle_gamma 70.58428131
_symmetry_Int_Tables_number 1
_chemical_formula_structural Rb2CoSe2
_chemical_formula_sum 'Rb4 Co2 Se4'
_cell_volume 326.13516780
_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
Rb Rb0 1 0.47274100 0.64525100 0.82749000 1.0
Rb Rb1 1 0.52725900 0.35474900 0.17251000 1.0
Rb Rb2 1 0.18223800 0.85474900 0.32749000 1.0
Rb Rb3 1 0.81776200 0.14525100 0.67251000 1.0
Co Co4 1 0.00000000 0.25000000 0.25000000 1.0
Co Co5 1 0.00000000 0.75000000 0.75000000 1.0
Se Se6 1 0.92317300 0.59647500 0.32669800 1.0
Se Se7 1 0.73022300 0.90352500 0.82669800 1.0
Se Se8 1 0.26977700 0.09647500 0.17330200 1.0
Se Se9 1 0.07682700 0.40352500 0.67330200 1.0
