HfC
Hafnium carbide · Hafnium monocarbide
Hafnium carbide is a thermodynamically stable, semiconducting ceramic known for its extreme heat resistance and structural reliability.
About Hafnium carbide
Hafnium carbide is a prominent member of the ultra-high-temperature ceramics family, characterized by its exceptional thermodynamic stability. As a semiconducting material, it maintains structural integrity under the most demanding thermal conditions, making it a critical subject of study in materials science.
Its unique combination of properties allows it to withstand extreme environments where conventional materials would fail. This compound is primarily utilized in high-performance aerospace components and specialized industrial applications requiring superior heat resistance and durability.
Key Properties
Cross-validated computational properties for Hafnium carbide, aggregated across 3 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.
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.
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.
StructuresCount of reported calculated crystal structures for this formula, including alternate polymorphs, source databases, and observed space groups.
Cross-Source DFT Agreement
How well independent DFT databases agree on the thermodynamics of HfC. Tight agreement means computed properties can be trusted without re-running calculations.
Agreement ScoreA normalized confidence score summarizing how closely independent DFT databases agree. Higher scores mean tighter cross-source agreement.
Hull SpreadDifference between the highest and lowest energy-above-hull values reported by comparable sources. Smaller spread means less thermodynamic disagreement.
Sources ComparedNumber and names of computational sources with comparable entries for this formula.
Space Group ConsensusWhether independent sources predict the same crystal symmetry for the lowest-energy structure.
Reported Structures
Lowest-energy structures reported for HfC, 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. |
|---|---|---|---|---|---|
| Fm-3m (No. 225) | cubic | 0.00 | 0.0000 | -28.672 | 12.71 |
| — | — | 0.00 | 0.0000 | -0.948 | — |
| Fm-3m (No. 225) | cubic | 0.00 | 0.0000 | -1.051 | — |
| — | — | 0.00 | 0.0000 | -0.948 | — |
| P63/mmc (No. 194) | hexagonal | 0.00 | 0.1972 | -28.475 | 12.57 |
| P63/mmc (No. 194) | hexagonal | 0.00 | 0.2099 | -0.841 | — |
| — | — | 0.00 | 0.2805 | -0.667 | — |
| F-43m (No. 216) | cubic | 0.38 | 0.6396 | -0.411 | — |
| F-43m (No. 216) | cubic | 0.30 | 0.6414 | -28.031 | 9.87 |
| — | — | 0.33 | 0.6438 | -0.304 | — |
| P-6m2 (No. 187) | hexagonal | 0.00 | 0.7529 | -0.298 | — |
| — | — | 0.00 | 0.7633 | -0.184 | — |
Applications
Where Hafnium carbide is used.
Patent Landscape
2 patents reference HfC or close compositional variants.
| Patent | Title | Assignee | Granted |
|---|---|---|---|
| 4084964 | High HfC-containing alloys | — | — |
| 11180419 | Method for preparation of dense HfC(Si)—HfB2 composite ceramic | — | — |
Frequently Asked Questions
Common questions about Hafnium carbide, answered from cross-validated data.
What is HfC?
Hafnium carbide is a thermodynamically stable, semiconducting ceramic known for its extreme heat resistance and structural reliability.
What is HfC used for?
What is the band gap of HfC?
Is HfC a metal, semiconductor, or insulator?
Is HfC thermodynamically stable?
What is the crystal structure of HfC?
What is the density of HfC?
How many polymorphs of HfC are known?
What elements does HfC contain?
Where does the data for HfC come from?
How It Compares
Within the ultra-high-temperature ceramics class.
Within the class of ultra-high-temperature ceramics, HfC stands out as a highly stable and well-documented compound compared to complex phases like Hf3N4 or HfN2. It shares the characteristic durability of ZrC, serving as a foundational material for high-temperature structural engineering.
Related Compounds
Other Ultra-High-Temperature Ceramics in the database.
Data sources & attribution
- materials_project — Data from the Materials Project (materialsproject.org). Cite: Jain et al., APL Materials 1, 011002 (2013). (CC-BY-4.0)
- oqmd — Data from the OQMD (oqmd.org). Cite: Saal et al., JOM 65, 1501 (2013); Kirklin et al., npj Comp. Mater. 1, 15010 (2015). (CC-BY-4.0)
- jarvis — Data from JARVIS (jarvis.nist.gov), NIST. Cite: Choudhary et al., npj Comp. Mater. 6, 173 (2020). (LicenseRef-US-Gov-PD)
- mpaloe — Data from MP-ALOE. Cite: Kuner et al., npj Comput. Mater. (2025), doi:10.1038/s41524-025-01834-9.
Analyze HfC in the Lattice Graph platform
Polymorph comparison, confidence scoring, supply-chain risk, and patent monitoring — across 85 source databases.
Explore the Platform →