Synthesis, spectral and redox switchable cubic NLO properties of chiral dinuclear iron cyanide/isocyanide-bridged complexes
- 化学化工－已发表论文 
Two chiral dinuclear cyanide/ isocyanide-bridged complexes (R)-[Cp(dppe) Fe-CN-Fe(dppp)Cp]PF6 (1[PF6]) and (R)-[Cp(dppe)Fe-NC-Fe(dppp)Cp]PF6 (2[PF6]), and their mono-oxidation products (R)-[Cp(dppe)Fe-II-CN-Fe-III(dppp)Cp] [PF6](2) (1[PF6](2)) and (R)-[Cp(dppe)Fe-III-NC-Fe-II(dppp)Cp][PF6](2) (2[PF6](2)) were synthesized and fully characterized. The electronic spectra of both the mixed-valence complexes 1[PF6](2) and 2[PF6](2) exhibit a strong and broad absorption band with two discernable peaks in the NIR region, which are attributed to Fe(II)-Fe(III) IVCT transitions. The attributions are supported by the DFT calculations. Under irradiation with a nanosecond laser at 1064 nm, the measured third-order NLO results of all four cyanide-bridged complexes showed that complexes 1(+) and 2(+) do not exhibit an NLO response, but their one-electron oxidation complexes 1(2+) and 2(2+) exhibit a strong NLO response due to a resonance enhanced effect. In addition, both complexes 1(2+) and 2(2+) display RSA and self-defocusing effects and show good optical limiting behavior in a broadband range.