Barium fluoride
Barium fluoride is an inorganic compound with the formula BaF2. It is a colorless solid that occurs in nature as the rare mineral frankdicksonite. Under standard conditions it adopts the fluorite structure and at high pressure the PbCl2 structure. Like CaF2, it is resilient to and insoluble in water.
| Identifiers | |
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3D model (JSmol) |
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| ChemSpider | |
| ECHA InfoCard | 100.029.189 |
PubChem CID |
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CompTox Dashboard (EPA) |
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| Properties | |
| BaF2 | |
| Molar mass | 175.324 g/mol |
| Appearance | white cubic crystals |
| Density | 4.893 g/cm3 |
| Melting point | 1,368 °C (2,494 °F; 1,641 K) |
| Boiling point | 2,260 °C (4,100 °F; 2,530 K) |
| 1.58 g/L (10 °C) 1.61 g/L (25 °C) | |
Solubility product (Ksp) |
1.84·10−7 |
| Solubility | soluble in methanol, ethanol |
| −51·10−6 cm3/mol | |
| Thermal conductivity | 10.9 W/(m·K) |
Refractive index (nD) |
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| Structure | |
| Fluorite (cubic), cF12 | |
| Fm3m, No. 225 | |
a = 0.62 nm | |
Formula units (Z) |
4 |
| Thermochemistry | |
Heat capacity (C) |
71.2 J/(mol·K) |
Std molar entropy (S⦵298) |
96.4 J/(mol·K) |
Std enthalpy of formation (ΔfH⦵298) |
−1207.1 kJ/mol |
Gibbs free energy (ΔfG⦵) |
−1156.8 kJ/mol |
| Hazards | |
| Occupational safety and health (OHS/OSH): | |
Main hazards |
Toxic |
| GHS labelling: | |
| Flash point | Non-flammable |
| Lethal dose or concentration (LD, LC): | |
LD50 (median dose) |
250 mg/kg, oral (rat) |
| Safety data sheet (SDS) | PubChem |
| Related compounds | |
Other anions |
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Other cations |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references | |
Above ca. 500 °C, BaF2 is corroded by moisture, but in dry environments it can be used up to 800 °C. Prolonged exposure to moisture degrades transmission in the vacuum UV range. It is less resistant to water than calcium fluoride, but it is the most resistant of all the optical fluorides to high-energy radiation, though its far ultraviolet transmittance is lower than that of the other fluorides. It is quite hard, very sensitive to thermal shock and fractures quite easily.