[{"from": "human", "value": "Design a molecule that meets the criteria outlined in the description. The molecule appears as pale yellow crystals. One of the most highly fluorescent substances. "}, {"from": "gpt", "value": "[C][=C][C][=C][C][=Branch1][Ring2][=C][Ring1][=Branch1][C][=Branch1][N][=C][C][=C][C][=C][C][Ring1][=Branch1][=N][Ring1][O][N].[Cl]"}]