[{"from": "human", "value": "Based on the given information, design a molecule that meets the desired specifications. The molecule is an aromatic hydrocarbon in coal tar, allied to naphthalene and anthracene. It is a white crystalline substance, C18H12, of strong blue fluorescence, but generally colored yellow by impurities."}, {"from": "gpt", "value": "[C][=C][C][=C][C][=Branch1][Ring2][=C][Ring1][=Branch1][C][=C][C][=C][Ring1][#Branch1][C][=C][C][=C][C][=C][C][=C][Ring1][=Branch1][Ring1][#Branch2]"}]