Key-Enabled Molecular Rotation Modulates Intramolecular Hydrogen Bonding Toward a turn-on Trace-Level N2H4 Sensor

1. Data Generation ProceduresFluorescence spectra:)Parameters: Excitation wavelength (λex= 390), emission range 400-800nm, slit widths (5-5 nm )Sample preparation: HEPES (2.3830 g) was dissolved in deionized water, and the pH was adjusted to 7.4 using 0.1 M NaOH and 0.1 M HCl. The solution was then brought to a final volume of 500 mL with deionized water, yielding a HEPES buffer solution (20.0 mM, 500 mL).242+3++2+UV-Vis absorption spectra:Instrument: UV-Vis spectrophotometer (Shimadzu UV-2600)Parameters: Wavelength range [200–800] nm, baseline corrected with solvent reference.NMR data:Instrument:JNM-ECS-400 MHz3 2. Data Processing MethodsSpectral data:Baseline correction applied using Origin 2025 with polynomial fitting/Savitzky-Golay smoothing.Fluorescence intensity normalized to [reference peak/solvent blank].NMR data:Processed with [MestReNova], including phase adjustment, and baseline correction. 3. Tabular Data (if applicable)Example: Fluorescence quantum yield calculations (Supplementary Table S1):Rows: 5 independent measurements.FF 4. Missing Data & ErrorsMissing data: No data points excluded; full spectra provided.Error ranges:Fluorescence intensity: ±1% (instrumental error, per manufacturer specifications).NMR chemical shifts: ±0.01 ppm (calibrated to TMS). 5. Data File DescriptionFile 1: SDG-2 Photophysical PropertiesContent: Wavelength (nm) vs. absorbance (a.u.).Format: opju （openable with Origin）Size: 157 KB. File 2: Aggregation-induced emission (AIE)-featureContent: Emission wavelength (nm) vs. intensity (a.u.).Format: opju （openable with Origin） File 3: Optical response of probe SDG-2 for hydrazineContent: Emission wavelength (nm) vs. intensity (a.u.).Format: opju （openable with Origin） File 4:Kinetic Study of SDG-2 ResponseContent: Emission wavelength (nm) vs. intensity (a.u.).Format: opju （openable with Origin） File 5:Selectivity and interference of SDG-2 toward N2H4Content: Emission wavelength (nm) vs. intensity (a.u.).Format: opju （openable with Origin） File 6: SDG-2 NMR-H/C MS-ESIContent: Raw  JNM-ECS-400 MHz NMR data.Software: MestReNova