[{"from": "human", "value": "Create a molecule that satisfies the conditions outlined in the description. Dull green odorless solid. Sinks and mixes slowly with water. (USCG, 1999)"}, {"from": "gpt", "value": "[C][C][=Branch1][C][=O][O-1].[C][C][=Branch1][C][=O][O-1].[Ni+2]"}]