[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule is a silicon coordination entity. It contains a hexafluorosilicate(2-)."}, {"from": "gpt", "value": "[F][Si-2][Branch1][C][F][Branch1][C][F][Branch1][C][F][Branch1][C][F][F].[Pb+2]"}]