1：Experimental Design and Method Selection:

The study involved preparing co-crystals via slow evaporation of mixed solutions, using halogen bonds (I···N interactions) to assemble components. Methods included infrared spectroscopy, single-crystal X-ray diffraction, fluorescence and Raman spectroscopy under high pressure, and theoretical simulations with Materials Studio.

2：Sample Selection and Data Sources:

Samples were co-crystals of bipyridine (BIPY) with iodopentafluorobenzene (IPFB), 1,4-diiodotetrafluorobenzene (DITFB), or 1,3,5-trifluoro-2,4,6-triiodobenzene (IFB), prepared at a 1:1 molar ratio in THF and n-hexane solvent. Data came from spectroscopic measurements and computational models.

3：List of Experimental Equipment and Materials:

Equipment included a Japan Science R-AXIS RAPID X-ray single-crystal diffractometer, Bruker VERTEX 80V FTIR spectrometer, diamond anvil cell (DAC) for high pressure, Horiba Jobin Yvon iHR320 spectrometer for fluorescence, LabRAM Aramis confocal Raman system, and computational software like Materials Studio and Gaussian 09. Materials were BIPY, IPFB, DITFB, IFB, THF, n-hexane, silicon oil, and ruby chips.

4：Materials were BIPY, IPFB, DITFB, IFB, THF, n-hexane, silicon oil, and ruby chips. Experimental Procedures and Operational Workflow:

4. Experimental Procedures and Operational Workflow: Co-crystals were formed by slow evaporation over 2-5 days. Single-crystal X-ray diffraction and IR spectroscopy characterized structures. High-pressure experiments used a DAC with silicon oil as pressure medium; pressure was measured via ruby fluorescence. Fluorescence and Raman spectra were collected at various pressures, and data were analyzed with software like Origin.

5：Data Analysis Methods:

Data analysis involved comparing I···N distances, spectroscopic shifts, and computational results from CASTEP and DFT calculations to interpret structural changes and emission behaviors.