CaAc(Cd2Ag)2
High-Entropy Materials HEAMP-ID: mp-3249812 · Space group: Amm2 (#38)
Basic Information
Formula
CaAc(Cd2Ag)2
MP-ID
mp-3249812
Elements
4
Sites
8
Density
7.7929
g/cm³
Volume
198.69
ų
Cell a
5.8179
Å
Cell b
5.8179
Å
Cell c
7.9781
Å
α Angle
90.00
°
β Angle
90.00
°
γ Angle
132.63
°
Space Group
Amm2
Point Group
mm2
Crystal System
Orthorhombic
Bravais Lattice
oC
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 |
|---|---|---|---|
| 11.09 | 7.9781 | 23.3 | (0,0,1) |
| 16.64 | 5.3277 | 13.9 | (1,-1,0) |
| 20.04 | 4.4306 | 8.4 | (1,-1,1) |
| 20.75 | 4.2807 | 2.5 | (1,0,0) |
| 22.29 | 3.9891 | 4.0 | (0,0,2) |
| 23.59 | 3.7720 | 20.6 | (1,0,1) |
| 27.94 | 3.1932 | 6.7 | (1,-1,2) |
| 30.63 | 2.9184 | 100.0 | (1,0,2) |
| 31.64 | 2.8281 | 27.0 | (2,-1,0) |
| 33.62 | 2.6655 | 82.0 | (2,-1,1) |
| 33.64 | 2.6639 | 9.2 | (2,-2,0) |
| 33.70 | 2.6594 | 3.2 | (0,0,3) |
| 35.53 | 2.5267 | 28.6 | (2,-2,1) |
| 37.81 | 2.3794 | 29.1 | (1,-1,3) |
| 38.52 | 2.3372 | 46.4 | (1,1,0) |
| 39.04 | 2.3071 | 30.2 | (2,-1,2) |
| 39.91 | 2.2590 | 35.7 | (1,0,3) |
| 40.21 | 2.2430 | 2.4 | (1,1,1) |
| 40.73 | 2.2153 | 20.0 | (2,-2,2) |
| 42.22 | 2.1403 | 2.7 | (2,0,0) |
| 43.79 | 2.0672 | 2.3 | (2,0,1) |
| 44.95 | 2.0166 | 1.3 | (1,1,2) |
| 45.48 | 1.9945 | 10.2 | (0,0,4) |
| 46.85 | 1.9391 | 3.3 | (3,-2,0) |
Energy Properties
Formation Energy/atom
-0.31574
eV/atom
Energy/atom
-25.16668
eV/atom
Energy above Hull
0.0032
eV/atom
Uncorrected Energy
-25.1667
eV/atom
Volume/atom
24.84
ų
c/a Ratio
1.3713
Electronic Properties
Metallic
Metal
Band Gap
0
eV
Direct Gap
No
CBM
N/A
eV
Magnetic Properties
Magnetic
No
Total Mag. Moment
0.0000
μB
Mag. Ordering
NM
Mag. Sites
0
Magnetization/Volume
0.000000
μB/ų
Elastic Properties
Elastic data not available
Feature Analysis
Composition Overview
Element Composition (atomic fraction)
Composition Info
Major / Matrix Element
Cd · 0.500
Element Family
4d-TM
Solute Fraction
0.500
Interstitial Fraction
0.000
High-Entropy Alloy Features
Composite Radar (normalized)
Element-Class Share
Mix Entropy ΔS/R
1.2130
HEA criterion (>1.0 = high entropy)
Mix Entropy ΔS
10.0849
J/mol·K
Ω Parameter
0.6201
Ω > 1.1 favors solid solution
Atomic Size Mismatch δr
12.897%
δr < 6.6% favors single-phase solid solution
Electronegativity Diff Δχ
0.3278
smaller = more stable mixing
VEC
9.250
valence electron concentration, affects phase stability
Mix Enthalpy ΔH_mix
-14.809
kJ/mol; negative = exothermic mixing
Entropy Norm
0.8750
SS Former
0
Phase Tendency
IM
Related Tasks
Related computation task IDs (1)
Citation & References
Materials Project Page
https://materialsproject.org/materials/mp-3249812
Reference Citation
The crystal structure and related material properties of CaAc(Cd2Ag)2 were obtained from the Materials Project database (MP-ID: mp-3249812, 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_CaAc(Cd2Ag)2
_symmetry_space_group_name_H-M 'P 1'
_cell_length_a 5.81786160
_cell_length_b 5.81786156
_cell_length_c 7.97813518
_cell_angle_alpha 90.00000000
_cell_angle_beta 90.00000000
_cell_angle_gamma 132.62652744
_symmetry_Int_Tables_number 1
_chemical_formula_structural CaAc(Cd2Ag)2
_chemical_formula_sum 'Ca1 Ac1 Cd4 Ag2'
_cell_volume 198.69103615
_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
Ca Ca0 1 0.92891071 0.07108929 0.75000000 1.0
Ac Ac1 1 0.06911687 0.93088313 0.25000000 1.0
Cd Cd2 1 0.36264188 0.63735812 0.04900193 1.0
Cd Cd3 1 0.36264188 0.63735812 0.45099807 1.0
Cd Cd4 1 0.64047231 0.35952769 0.56260068 1.0
Cd Cd5 1 0.64047231 0.35952769 0.93739932 1.0
Ag Ag6 1 0.77855979 0.22144021 0.25000000 1.0
Ag Ag7 1 0.21718226 0.78281774 0.75000000 1.0
