Cu4O4
Cu4O4 has a DFT band gap of 0.02 eV across 40 reported structures in 14 space groups; its lowest-energy polymorph is tetragonal (P42/mmc (No. 131)). Cross-validated across 4 computational databases.
At a glance
Key Properties
Cross-validated computational properties for Cu4O4, aggregated across 4 databases.
Band GapEnergy needed to move an electron from the valence band to the conduction band. Lower or zero values tend to behave more metallic; larger gaps are more insulating or semiconducting.
0.02 eV
Range across DFT structures
Energy Above HullThermodynamic distance from the most stable set of competing phases. 0 eV/atom is on the convex hull; small positive values may still be experimentally accessible.
0.000 eV/atom
Best (lowest) across sources
StabilityA plain-language summary of the best reported energy-above-hull result. It reflects whether the lowest-energy structure is on, near, or far from the stability hull.
On hull (stable)
2 DFT sources
StructuresCount of reported calculated crystal structures for this formula, including alternate polymorphs, source databases, and observed space groups.
40
4 databases, 14 space groups
Crystallography
Reported Structures
Lowest-energy structures reported for Cu4O4, ranked by energy above hull.
| Space GroupSymmetry classification of the crystal arrangement. The number is the international space-group index. | Crystal SystemBroad lattice family, such as cubic, tetragonal, monoclinic, or triclinic, derived from unit-cell symmetry. | Band Gap (eV)Electronic gap calculated for this specific reported structure, measured in electronvolts. | E above hull (eV/atom)Thermodynamic distance from the convex hull for this structure, normalized per atom. Lower is generally more stable. | E/atom (eV)Computed total energy normalized per atom. Use energy above hull, not this value alone, when comparing stability. | Density (g/cm³)Mass per relaxed crystal volume, reported in grams per cubic centimeter. |
|---|---|---|---|---|---|
| P42/mmc (No. 131) | tetragonal | 0.00 | 0.0000 | -5.466 | 6.16 |
| C2/c (No. 15) | monoclinic | 0.00 | 0.0003 | -5.466 | 5.94 |
| Cccm (No. 66) | orthorhombic | 0.00 | 0.0011 | -5.465 | 5.97 |
| Pnma (No. 62) | orthorhombic | 0.02 | 0.1528 | -5.314 | 4.69 |
| Fm-3m (No. 225) | cubic | 0.00 | 0.1711 | -5.295 | 6.97 |
| P42/nmc (No. 137) | tetragonal | 0.00 | 0.1795 | -5.287 | 5.06 |
| P4/mmm (No. 123) | tetragonal | 0.00 | 0.2776 | -5.189 | 5.89 |
| Pm-3m (No. 221) | cubic | 0.00 | 0.3354 | -5.131 | 6.47 |
| I4/mmm (No. 139) | tetragonal | 0.00 | 0.5894 | -4.877 | 3.73 |
| No. 0 | unknown | — | — | — | 1.63 |
| No. 0 | unknown | — | — | — | 1.61 |
| — | — | — | — | — | 5.74 |
Reference
Frequently Asked Questions
Common questions about Cu4O4, answered from cross-validated data.
What is the band gap of Cu4O4?
Cu4O4 has a DFT-computed band gap of 0.02 eV across 40 reported structures.
More questions
Is Cu4O4 a metal, semiconductor, or insulator?
With a near-zero band gap it behaves as a (semi)metal.
Is Cu4O4 thermodynamically stable?
Yes — Cu4O4 sits on the convex hull (energy above hull 0 eV/atom), i.e. on hull (stable).
What is the crystal structure of Cu4O4?
The lowest-energy reported polymorph of Cu4O4 is tetragonal symmetry, space group P42/mmc (No. 131).
What is the density of Cu4O4?
The computed density of the ground-state structure of Cu4O4 is 6.16 g/cm³.
How many polymorphs of Cu4O4 are known?
40 structures of Cu4O4 are reported across 4 databases, spanning 14 distinct space groups.
What elements does Cu4O4 contain?
Cu4O4 contains Cu and O (2 elements).
Where does the data for Cu4O4 come from?
Cu4O4 data is cross-referenced from materials_project, cod, omat24, aflow.
Explore
Related Compounds
Other Conversion Oxide Anodes in the database.
Data sources & attribution
- materials_project — Data from the Materials Project. Cite: Jain et al., APL Materials 1, 011002 (2013).
- cod — Data from the Crystallography Open Database. Cite: Grazulis et al., Nucleic Acids Res. 40, D420 (2012).
- omat24 — Data from OMat24 (Meta FAIR). Cite: Barroso-Luque et al., arXiv 2410.12771 (2024).
- aflow — Data from AFLOW. Cite: Curtarolo et al., Comp. Mater. Sci. 58, 218 (2012).
Analyze Cu4O4 in the Lattice Graph platform
Polymorph comparison, confidence scoring, supply-chain risk, and patent monitoring — across 53 integrated data sources.
Explore the Platform →