# DFT Cross-Check — Tier 3 Engine Panel (Public Export)

Date: 2026-05-07T10:22:44Z
Originator: FluxMateria
Machine-readable artifacts: `dft_crosscheck_tier3_engine_panel.json`, `dft_crosscheck_tier3_engine_panel.csv`

## Scope

Tier 3 — full ~40-property characterization returned from one composition-only engine call, on the same 15 materials as the Tier 1 / Tier 2 head-to-head comparisons. DFT-side comparison is architectural (workflow count + wall-time per workflow); see the page text for details.

**Materials:** 15  
**Properties per material:** 40

## Property Classes

### Structural (5 properties)

- Lattice constant a (Å)
- Atomic volume (ų)
- Density (g/cm³)
- Coordination number
- Crystal structure

### Mechanical (8 properties)

- Bulk modulus B (GPa)
- Shear modulus G (GPa)
- Young's modulus E (GPa)
- Poisson ratio ν
- Elastic constant C₁₁ (GPa)
- Elastic constant C₁₂ (GPa)
- Elastic constant C₄₄ (GPa)
- Hardness (GPa)

### Thermal (10 properties)

- Cohesive energy (eV/atom)
- Formation enthalpy ΔHf (eV/atom)
- Debye temperature θ_D (K)
- Sound velocity vs (m/s)
- Thermal expansion α (ppm/K)
- Heat capacity Cv (J/(mol·K))
- Heat capacity Cp (J/(mol·K))
- Thermal conductivity κ (W/(m·K))
- Grüneisen parameter γ
- Melting point Tm (K)

### Electronic (8 properties)

- Band gap Eg (eV)
- Effective mass m*/me
- Electron mobility μe (cm²/(V·s))
- Hole mobility μh (cm²/(V·s))
- Conductivity σ (S/m)
- Electron affinity (eV)
- Ionization energy (eV)
- Work function W (eV)

### Optical (5 properties)

- Refractive index n
- Dielectric constant ε
- Absorption coefficient α (/cm)
- Reflectivity R
- Color

### Magnetic (4 properties)

- Magnetic moment μ (μB/atom)
- Saturation magnetization Ms (A/m)
- Curie temperature Tc (K)
- Magnetic susceptibility χ

## Example: Engine output for Si (one call, ~3 ms)

**Structural**

| Property | Value | Unit |
|---|---|---|
| Lattice constant a | 5.431 | Å |
| Atomic volume | 20.02 | ų |
| Density | 2.33 | g/cm³ |
| Coordination number | 4 |  |
| Crystal structure | diamond |  |

**Mechanical**

| Property | Value | Unit |
|---|---|---|
| Bulk modulus B | 98.04 | GPa |
| Shear modulus G | 68.5 | GPa |
| Young's modulus E | 166.7 | GPa |
| Poisson ratio ν | 0.2167 |  |
| Elastic constant C₁₁ | 189.4 | GPa |
| Elastic constant C₁₂ | 52.38 | GPa |
| Elastic constant C₄₄ | 78.77 | GPa |
| Hardness | 12.4 | GPa |

**Thermal**

| Property | Value | Unit |
|---|---|---|
| Cohesive energy | 4.572 | eV/atom |
| Formation enthalpy ΔHf | 0 | eV/atom |
| Debye temperature θ_D | 619.7 | K |
| Sound velocity vs | 8283 | m/s |
| Thermal expansion α | 2.6 | ppm/K |
| Heat capacity Cv | 20 | J/(mol·K) |
| Heat capacity Cp | 20 | J/(mol·K) |
| Thermal conductivity κ | 163.6 | W/(m·K) |
| Grüneisen parameter γ | 1.453 |  |
| Melting point Tm | 1539 | K |

**Electronic**

| Property | Value | Unit |
|---|---|---|
| Band gap Eg | 1.119 | eV |
| Effective mass m*/me | 0.2602 |  |
| Electron mobility μe | 1411 | cm²/(V·s) |
| Hole mobility μh | 452.6 | cm²/(V·s) |
| Conductivity σ | 0.0003307 | S/m |
| Electron affinity | 4.05 | eV |
| Ionization energy | 5.17 | eV |
| Work function W | 4.85 | eV |

**Optical**

| Property | Value | Unit |
|---|---|---|
| Refractive index n | 3.46 |  |
| Dielectric constant ε | 11.71 |  |
| Absorption coefficient α | 3442 | /cm |
| Reflectivity R | 0.3001 |  |
| Color | black |  |

**Magnetic**

| Property | Value | Unit |
|---|---|---|
| Magnetic moment μ | 0 | μB/atom |
| Saturation magnetization Ms | 0 | A/m |
| Curie temperature Tc | 0 | K |
| Magnetic susceptibility χ | -1.054e-05 |  |

## Notes

- All values come from a single composition-only engine call per material. Engine wall time is ~3 ms per material; the entire 15-material panel runs in under 50 ms.
- Per-property accuracy benchmarks against experiment are reported on dedicated pages (band gap, mobility, Curie temperature, melting, elastic moduli, etc.). The head-to-head DFT comparison for the 15-material set is in Tiers 1 and 2.
- Reproducing the same property suite from DFT requires 6+ separate workflows (SCF + EOS + DFPT phonons + Boltzmann transport + LR-TDDFT + magnetic Monte Carlo) running for ~1–3 weeks of CPU time per material at production quality.