Synthesis, structure and antiproliferative and optical activities of two new biphenyl-derived Schiff bases [unknown]

Xue-Jie Tan, Ling-Yao Zhang, Yuan-Kai Sun, Xue-Min Zhou
2019 unpublished
The explanations for the emission spectra of the title compounds. For the fluorescence spectra of 3-BEHMI, four functionals render the same relative intensity ratio predication of the two bands, i.e. the intense peak has lower energy while the weak peak has higher energy (Figs S13-S16), which is exactly reverse with experimental results (Fig. 6b) . On the point of band maximum positions of the simulated spectra, the most reliable result is that performed with B3LYP (Fig. S13). The emission
more » ... . The emission wavelengths in ethanol solution are 338 and 440 nm; the wavelengths in the gas phase are 335 and 432 nm, both fall into the experimental scopes (310-340 nm and 400-450 nm). However, the emission energies using other functionals are quite different and significantly worse. Sometimes the reliable result is obtained only in the gas phase (PBE1PBE, Fig. S15); and sometimes considering solvent effects may result in better simulations (M062X and WB97XD, Fig. S14 and S16) than that in the gas phase, yet only one band is reliable. At last, the results from TD-DFT/B3LYP/PCM approach were used for MO analysis. 3-BEHEI shows one strong fluorescence band between 310-350 nm, upon excitation at 200, 220 and 280 nm (Fig. 7b) . None of the calculated emission spectra represent a good approximation (Figs S17-S20). The influences of the functionals and the solvent corrections on the calculated emission energies are rather dramatic. For different functionals, the deviations may exceed 58 nm (M062X and
doi:10.1107/s2053229618017989/ov3117sup4.pdf fatcat:heepiqadebempp2i4w2dlr225y