1：Experimental Design and Method Selection:

The study involved the synthesis of a diarylethene derivative and investigation of its photochromism and fluorescent properties in methanol solution.

2：Sample Selection and Data Sources:

The derivative was synthesized and its interaction with various metal ions was studied.

3：List of Experimental Equipment and Materials:

Materials were purchased commercially and used without further purification. Instruments included a Bruker AV400 spectrometer, Agilent 1100 ion trap MSD spectrometer, WRS-1B melting point apparatus, Agilent 8453 UV-visible spectrophotometer, MUA-165 UV lamp, MVL-210 visible lamp, Hitachi F-4600 fluorescence spectrophotometer, and Absolute PL Quantum Yield Spectrometer QYC11347-

4：Experimental Procedures and Operational Workflow:

The derivative's photochromism and fluorescent properties were measured under UV/vis light irradiation and in the presence of various metal ions.

5：Data Analysis Methods:

The quantum yields of cyclization and cycloreversion were determined, and the binding constant (Ka) of the derivative with Cd2+ was calculated.