[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is a mineral with formula of CaMn2+3Mn2+Si5O15 or CaMn3Mn(Si5O15). The corresponding IMA (International Mineralogical Association) number is IMA2019 s.p.. The IMA symbol is Rdn."}, {"from": "gpt", "value": "[O-1][Si][=Branch1][C][=O][O-1].[Mn+2]"}]