Molecular Structure of Magnesium fluosilicate (CAS NO.16949-65-8):

IUPAC Name: magnesium hexafluorosilicon(2-) 
Empirical Formula: F₆MgSi
Molecular Weight: 166.3809192
EINECS: 241-022-2
Melting point: 120°C
Boiling Point: >120°C
Density 1.788g/cm³
Product Categories: Inorganics
InChI
InChI=1/F6Si.Mg/c1-7(2,3,4,5)6;/q-2;+2
Smiles
[Si-2](F)(F)(F)(F)(F)F.[Mg+2]

Reported in EPA TSCA Inventory.

Moderately toxic by ingestion. When heated to decomposition it emits toxic vapors of magnesium and F⁻.
Hazard Codes:
T: Toxic
Risk Statements:
R25 Toxic if swallowed.
Safety Statements:
S45 In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.)
S24/25: Avoid contact with skin and eyes.
Attention:
1. Health Hazard: Highly toxic, may be fatal if inhaled, swallowed or absorbed through skin. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
2. Fire Hazard Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Containers may explode when heated. Runoff may pollute waterways.

DOT Classification:  6.1; Label: KEEP AWAY FROM FOOD

  Magnesium fluosilicate , with CAS number of 16949-65-8, can be called silicate(2-), hexafluoro-, magnesium (1:1) ; Magnesium hexafluorosilicate(2-) (1:1) Fluosilicate de magnesium . Magnesium fluosilicate (CAS NO.16949-65-8) is used for concrete curing agent and water-proofing agent and for surface treatment and manufacture different building ceramic.