[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule is a crystalline solid. Decomposes at 120 \u00b0C. Contact may cause slight irritation to skin, eyes, and mucous membranes. May be slightly toxic by ingestion. Used to make other chemicals."}, {"from": "gpt", "value": "[F][Si-2][Branch1][C][F][Branch1][C][F][Branch1][C][F][Branch1][C][F][F].[Mg+2]"}]