Magnesium fluoride represented by the chemical formula MgF₂ or F₂Mg that bears the IUPAC name magnesium difluoride is a stable compound that is not hygroscopic as such and slightly soluble in dilute acids (like nitric acid) but insoluble in alcohol. It is an ionic compound of magnesium and fluorine and non-polar in gaseous phase ^{[1, 8]}. In UV light it fluoresces purple ^[8].

Magnesium Fluoride Identification
CAS Number	7783-40-6 [1]
PubChem CID	24546 [1]
ChemSpider ID	22952 [2]
EC Number	231-995-1 [3]

How to Make It

Magnesium fluoride is synthesized by a reaction between magnesium oxide and ammonium bifluoride ^[8].

MgO + (NH₄)HF₂ = MgF₂ + NH₃ + H₂O

Properties and Characteristics of Magnesium Fluoride

General Properties
Molar mass/molecular weight	62.302 g/mol [1]
Physical Properties
Color/appearance	White crystals [3]
Melting point/freezing point	1260°C, 2300°F [3]
Boiling point	2260°C, 4100°F [3]
Density	3.2 g cm-3 [3]
State of matter at room temperature (normal phase)	Solid [3]
Refractive index	1.4 [3]
Thermal conductivity	28 W/m-K [3]
Hardness (Mohs scale)	6 [10]
Specific heat capacity	0.92 X 103 J/(kg.deg C) [10]
Chemical Properties
Solubility in water	No [3]
pH	N/A [11]
Atomic Properties
Crystal structure	Tetragonal [12]

Magnesium Fluoride Uses

1. In anti-reflective, multi-layer optical coatings on glass ^[4].
2. As a durable material for lenses that can be used in UV and IR light eliminating birefringence ^[5].
3. MgF₂ windows are widely used in the deep and vacuum UV regions. They are durable and produce minimal aberrations ^[9].

Is It Dangerous

The compound can be acutely toxic if swallowed. It is a cause of serious eye, skin and respiratory tract irritation. So inhalation should be avoided ^[7].

Magnesium Fluoride (MgF₂) Price

10 g of the inorganic compound powder costs around $15 ^[6].

References
1. Magnesium Fluoride (MgF2) – Pubchem.ncbi.nlm.nih.gov
2. Sellaite – Chemspider.com
3. Magnesium Fluoride – Americanelements.com
4. MAGNESIUM FLUORIDE MGF₂ OVERVIEW – Materion.com
5. Magnesium Fluoride Plano-Convex Lenses, Uncoated – Thorlabs.com
6. Magnesium fluoride, powder – Oakwoodchemical.com
7. Magnesium Fluoride – Chemicalbook.com
8. Magnesium Fluoride – Cameo.mfa.org
9. Magnesium Fluoride Windows – Thorlabs.com
10. Magnesium Fluoride (MgF2) – Janis.com
11. Magnesium Fluoride – Espimetals.com
12. Material MgF₂ – Materialsproject.org