1：Experimental Design and Method Selection

The study involved the synthesis of 2-APB by reacting 2-aminopyridine with benzilic acid in methanol, followed by slow evaporation for crystal growth. Structural characterization was performed using single crystal X-ray diffraction, FT-IR, FT-NMR, and UV-Vis spectroscopy. Computational studies were conducted using B3LYP method at 6-311+G(d,p) level for geometry optimization, NBO, Mulliken atomic charge, and HOMO-LUMO analyses.

2：Sample Selection and Data Sources

2-aminopyridine and benzilic acid were used as reactants. Single crystals of 2-APB were grown from methanol solution.

3：List of Experimental Equipment and Materials

Perkin Elmer 240C elemental analyzer, SHIMADZU 1601 UV-Vis spectrophotometer, FT-IR 8000 spectrophotometer, Horiba Jobin Yvon Lab Ram-HR Raman spectrometer, BRUKER AV III 500 MHz NMR spectrometer, Oxford Xcalibur Gemini EOS CCD diffractometer, NETZSCH 409 C/CD TGA/DTA instrument, Nd:YAG laser for Z-scan experiments.

4：Experimental Procedures and Operational Workflow

The synthesis involved mixing equimolar solutions of 2-aminopyridine and benzilic acid in methanol, stirring for 6 hours, and allowing the solution to evaporate slowly for crystal growth. Characterization techniques included elemental analysis, spectroscopic analyses, thermal analysis, and single crystal X-ray diffraction. Computational studies were performed using Gaussian'09 and Crystal Explorer 3.1 software.

5：Data Analysis Methods

Data from spectroscopic and diffraction studies were analyzed to confirm the structure and properties of 2-APB. Computational data were analyzed to understand molecular interactions and properties.