Si3N4
Si3N4 has a DFT band gap of 1.43–4.84 eV across 44 reported structures in 11 space groups; its reference structure is hexagonal (P63/m (No. 176)). Cross-validated across 3 computational databases.
At a glance
Key Properties
Cross-validated computational properties for Si3N4, 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.
1.43–4.84 eV
Range across DFT structures · ground state: insulator
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.
Stable
3 DFT sources
StructuresCount of reported calculated crystal structures for this formula, including alternate polymorphs, source databases, and observed space groups.
44
3 databases, 11 space groups
Validation
Cross-Source DFT Agreement
How well independent DFT databases agree on the thermodynamics of Si3N4. 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.
1.00 / 1.00
Trust tier: high
Hull SpreadDifference between the highest and lowest energy-above-hull values reported by comparable sources. Smaller spread means less thermodynamic disagreement.
0.000 eV
EAH spread across sources
Sources ComparedNumber and names of computational sources with comparable entries for this formula.
3
jarvis, materials_project, oqmd
Space Group ConsensusWhether independent sources predict the same crystal symmetry for the lowest-energy structure.
All match
Crystallography
Reported Structures
Lowest-energy structures reported for Si3N4, 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. |
|---|---|---|---|---|---|
| P63/m (No. 176) | hexagonal | 4.46 | 0.0000 | -1.192 | — |
| — | — | 4.32 | 0.0000 | -1.215 | — |
| P63/m (No. 176) | hexagonal | 4.25 | 0.0000 | -10.298 | 3.20 |
| — | — | 4.42 | 0.0001 | -1.214 | — |
| — | — | 4.42 | 0.0001 | -1.214 | — |
| — | — | 4.82 | 0.0003 | -1.214 | — |
| — | — | 4.71 | 0.0006 | -1.214 | — |
| P31c (No. 159) | trigonal | 4.66 | 0.0035 | -10.294 | 3.19 |
| P31c (No. 159) | trigonal | 4.84 | 0.0039 | -1.189 | — |
| I-43d (No. 220) | cubic | 4.28 | 0.0828 | -1.110 | — |
| — | — | 4.22 | 0.0994 | -1.115 | — |
| I-43d (No. 220) | cubic | 4.03 | 0.0995 | -10.198 | 3.41 |
Synthesis
Synthesis Routes
Literature-extracted synthesis procedures targeting Si3N4.
Solid State
Procedure available · ceder_solid_state
Intellectual Property
Patent Landscape
15 patents reference Si3N4 or close compositional variants.
| Patent | Title | Assignee | Granted |
|---|---|---|---|
| 7638200 | Process for making dense mixed metal Si3N4 targets | — | — |
| 8658432 | Si/Si3N4 system nanosized particles, biosubstance labeling agent employing the nanosized particles, and method | — | — |
| 7622152 | MoSi2-Si3N4 composite coating and manufacturing method thereof | — | — |
| 6284690 | Si3N4 ceramic, Si-base composition for production thereof and processes for producing these | — | — |
| 6391811 | Pest resistant MoSi2-based materials containing in-situ grown &bgr;-Si3N4 whiskers | — | — |
| 6544917 | Si3N4 ceramic, Si-base composition for its production, and method for its production | — | — |
| 9302944 | Si3N4 insulator material for corona discharge igniter systems | — | — |
| 6617272 | Si3N4 sintered body with high thermal conductivity and method for producing the same | — | — |
| 7446066 | Reverse reaction sintering of Si3N4/SiC composites | — | — |
| 8673795 | Si3N4 insulator material for corona discharge igniter systems | — | — |
Reference
Frequently Asked Questions
Common questions about Si3N4, answered from cross-validated data.
What is the band gap of Si3N4?
Si3N4 has a DFT-computed band gap of 1.43–4.84 eV across 44 reported structures. Standard DFT underestimates band gaps, so the measured gap is typically larger.
More questions
Is Si3N4 a metal, semiconductor, or insulator?
DFT predicts a wide band gap of up to 4.84 eV (an insulator or wide-band-gap material).
Is Si3N4 thermodynamically stable?
Yes — Si3N4 sits on the convex hull (energy above hull 0 eV/atom), i.e. stable.
What is the crystal structure of Si3N4?
The reference structure of Si3N4 is hexagonal symmetry, space group P63/m (No. 176).
How many polymorphs of Si3N4 are known?
44 structures of Si3N4 are reported across 3 databases, spanning 11 distinct space groups.
How is Si3N4 synthesized?
Literature-reported routes for Si3N4 include solid state.
What elements does Si3N4 contain?
Si3N4 contains N and Si (2 elements).
Where does the data for Si3N4 come from?
Si3N4 data is cross-referenced from jarvis, oqmd, materials_project.
Explore
Related Compounds
Other Silicon Anode Materials in the database.
Data sources & attribution
- jarvis — Data from JARVIS (jarvis.nist.gov), NIST. Cite: Choudhary et al., npj Comp. Mater. 6, 173 (2020). (LicenseRef-US-Gov-PD)
- 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)
- materials_project — Data from the Materials Project (materialsproject.org). Cite: Jain et al., APL Materials 1, 011002 (2013). (CC-BY-4.0)
Analyze Si3N4 in the Lattice Graph platform
Polymorph comparison, confidence scoring, supply-chain risk, and patent monitoring — across 85 source databases.
Explore the Platform →