[{"from": "human", "value": "Given SMILES, write its poly dispersity index at room temperature and atmospheric pressure. ->  CC1=CC([Si]2(CCCCCCCC)CCCCCCCC)=C(S1)C3=C2C(S4)=C(S3)C5=C4C6=C([Si]5(CCCCCCCC)CCCCCCCC)C=C(C7=C(F)C(F)=C(C)C8=NSN=C87)S6\n"}, {"from": "gpt", "value": " 1.5\n"}]