Ca(CuO2)2

High-Entropy Materials HEA Traditional Materials TRA

MP-ID: mp-1047358 · Space group: Cmcm (#63)

Materials Project API

Basic Information

Formula

Ca(CuO2)2

MP-ID

mp-1047358

Elements

Sites

Density

5.2269

g/cm³

Volume

146.88

Å³

Cell a

5.1648

Cell b

5.1648

Cell c

9.5177

α Angle

90.00

β Angle

90.00

γ Angle

144.65

Space Group

Cmcm

Point Group

mmm

Crystal System

Orthorhombic

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
18.03	4.9210	1.8	(1,-1,0)
18.65	4.7589	27.2	(0,0,2)
20.32	4.3713	7.1	(1,-1,1)
26.05	3.4209	6.0	(1,-1,2)
29.90	2.9880	21.4	(1,0,0)
31.38	2.8508	32.3	(1,0,1)
33.61	2.6665	100.0	(1,-1,3)
35.47	2.5305	27.0	(1,0,2)
36.52	2.4605	26.4	(2,-2,0)
39.76	2.2669	40.4	(2,-1,0)
40.92	2.2052	50.4	(2,-1,1)
41.31	2.1856	1.7	(2,-2,2)
41.52	2.1752	7.9	(1,0,3)
42.19	2.1422	10.1	(1,-1,4)
44.26	2.0466	53.1	(2,-1,2)
48.93	1.8614	7.8	(1,0,4)
49.41	1.8444	5.5	(2,-1,3)
51.47	1.7754	8.6	(1,-1,5)
56.00	1.6422	6.7	(3,-2,1)
56.03	1.6413	2.7	(2,-1,4)
57.40	1.6054	25.0	(1,0,5)
58.15	1.5863	13.0	(0,0,6)
58.68	1.5734	10.3	(3,-2,2)
58.90	1.5680	21.4	(1,1,0)

Get direct link

Energy Properties

Formation Energy/atom

-1.53282

eV/atom

Energy/atom

-5.81795

eV/atom

Energy above Hull

0.1774

eV/atom

Uncorrected Energy

-5.4254

eV/atom

Volume/atom

10.49

Å³

c/a Ratio

1.8428

Electronic Properties

Metallic

Metal

Band Gap

Direct Gap

CBM

N/A

Magnetic Properties

Magnetic

Total Mag. Moment

0.0017

μB

Mag. Ordering

Mag. Sites

Magnetization/Volume

0.000010

μB/Å³

Elastic Properties

Elastic data not available

Feature Analysis

Composition Overview

Element Composition (atomic fraction)

Composition Info

Major / Matrix Element

O · 0.571

Element Family

Metalloid-Nonmetal

Solute Fraction

0.429

Interstitial Fraction

0.000

High-Entropy Alloy Features

Composite Radar (normalized)

Element-Class Share

Mix Entropy ΔS/R

0.9557

HEA criterion (>1.0 = high entropy)

Mix Entropy ΔS

7.9457

J/mol·K

Ω Parameter

2.0114

Ω > 1.1 favors solid solution

Atomic Size Mismatch δr

50.317%

δr < 6.6% favors single-phase solid solution

Electronegativity Diff Δχ

0.9520

smaller = more stable mixing

VEC

5.714

valence electron concentration, affects phase stability

Mix Enthalpy ΔH_mix

-2.286

kJ/mol; negative = exothermic mixing

Entropy Norm

0.8699

SS Former

Phase Tendency

Traditional Material Features

ROM Blended-Feature Radar

Rating & Classification

Tier

Score

0.444

Family

O-rich Multi-Component

Matrix Element

O · 0.571

Related Tasks

Related computation task IDs (3)

aaachpjz aaadvedc aaaecrtr

Citation & References

Materials Project Page

https://materialsproject.org/materials/mp-1047358

Reference Citation

The crystal structure and related material properties of Ca(CuO2)2 were obtained from the Materials Project database (MP-ID: mp-1047358, 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…

Style: Ball & Stick | Drag to rotate · Scroll to zoom · Right-click to pan

Raw CIF Data

# generated using pymatgen
data_Ca(CuO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.16474546
_cell_length_b   5.16474546
_cell_length_c   9.51771800
_cell_angle_alpha   90.00000000
_cell_angle_beta   90.00000000
_cell_angle_gamma   144.65243010
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ca(CuO2)2
_chemical_formula_sum   'Ca2 Cu4 O8'
_cell_volume   146.87921233
_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
  Ca  Ca0  1  0.60551300  0.39448700  0.75000000  1.0
  Ca  Ca1  1  0.39448700  0.60551300  0.25000000  1.0
  Cu  Cu2  1  0.13682700  0.86317300  0.06927400  1.0
  Cu  Cu3  1  0.86317300  0.13682700  0.93072600  1.0
  Cu  Cu4  1  0.13682700  0.86317300  0.43072600  1.0
  Cu  Cu5  1  0.86317300  0.13682700  0.56927400  1.0
  O  O6  1  0.77258900  0.22741100  0.39441100  1.0
  O  O7  1  0.22741100  0.77258900  0.60558900  1.0
  O  O8  1  0.22741100  0.77258900  0.89441100  1.0
  O  O9  1  0.77258900  0.22741100  0.10558900  1.0
  O  O10  1  0.06130100  0.93869900  0.25000000  1.0
  O  O11  1  0.93869900  0.06130100  0.75000000  1.0
  O  O12  1  0.50000000  0.50000000  0.00000000  1.0
  O  O13  1  0.50000000  0.50000000  0.50000000  1.0

Get direct link