Ca12O28Si8
Xonotlite · Calcium silicate hydrate
Xonotlite is a naturally occurring calcium silicate mineral that is frequently synthesized for industrial use. It is highly valued for its excellent thermal stability and structural integrity, making it an ideal material for high-temperature insulation and fireproofing applications.
CaOSi
Overview
Key Properties
Cross-validated computational properties for Xonotlite, 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.
4.43–4.66 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.
0.002 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.
Near hull (likely stable)
1 DFT source
StructuresCount of reported calculated crystal structures for this formula, including alternate polymorphs, source databases, and observed space groups.
5
3 databases, 3 space groups
Crystallography
Reported Structures
Lowest-energy structures reported for Ca12O28Si8, 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. |
|---|---|---|---|---|---|
| Ima2 (No. 46) | orthorhombic | 4.66 | 0.0024 | -7.754 | 2.90 |
| P21/c (No. 14) | monoclinic | 4.43 | 0.0088 | -7.748 | 2.89 |
| No. 0 | unknown | — | — | — | 0.74 |
| No. 0 | unknown | — | — | — | 0.75 |
| Ima2 (No. 46) | — | — | — | — | — |
Uses
Applications
Where Xonotlite is used.
Thermal insulation materialsFire-resistant building boardsReinforcing filler in polymersCement and concrete additives
Reference
Frequently Asked Questions
Common questions about Xonotlite, answered from cross-validated data.
What is Ca12O28Si8?
Xonotlite is a naturally occurring calcium silicate mineral that is frequently synthesized for industrial use. It is highly valued for its excellent thermal stability and structural integrity, making it an ideal material for high-temperature insulation and fireproofing applications.
What is Ca12O28Si8 used for?
Xonotlite (Ca12O28Si8) is used in thermal insulation materials, fire-resistant building boards, reinforcing filler in polymers, and cement and concrete additives.
What is the band gap of Ca12O28Si8?
Xonotlite (Ca12O28Si8) has a DFT-computed band gap of 4.43–4.66 eV across 5 reported structures.
Is Ca12O28Si8 a metal, semiconductor, or insulator?
With a wide band gap up to 4.66 eV it is an insulator / wide-band-gap material.
Is Ca12O28Si8 thermodynamically stable?
Xonotlite (Ca12O28Si8) has a lowest energy above hull of 0.002 eV/atom (near hull (likely stable)).
What is the crystal structure of Ca12O28Si8?
The lowest-energy reported polymorph of Xonotlite (Ca12O28Si8) is orthorhombic symmetry, space group Ima2 (No. 46).
What is the density of Ca12O28Si8?
The computed density of the ground-state structure of Xonotlite (Ca12O28Si8) is 2.90 g/cm³.
How many polymorphs of Ca12O28Si8 are known?
5 structures of Ca12O28Si8 are reported across 3 databases, spanning 3 distinct space groups.
What elements does Ca12O28Si8 contain?
Xonotlite (Ca12O28Si8) contains Ca, O, and Si (3 elements).
Where does the data for Ca12O28Si8 come from?
Ca12O28Si8 data is cross-referenced from materials_project, cod, aflow.
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).
- aflow — Data from AFLOW. Cite: Curtarolo et al., Comp. Mater. Sci. 58, 218 (2012).
Analyze Ca12O28Si8 in the Lattice Graph platform
Polymorph comparison, confidence scoring, supply-chain risk, and patent monitoring — across 53 integrated data sources.
Explore the Platform →