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Updated: May 23, 2026
Determining Surface Areas and Pore Volumes of Metal-Organic Frameworks
Published on: March 8, 2024
Precise construction of nitrogen-containing nanohoop isomers: metal-induced modulation of nonlinear optical
Lin-Lin Zhou1, Xiao Huang1, Hao-Ran Qiu1
1School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, 7989 Weixing Road, Changchun 130012, China.
Abstract:
Carbon nanorings have attracted considerable attention due to their unique cyclic architectures and tunable electronic properties. To elucidate the structure-property relationship between configurational isomerism and nonlinear optical (NLO) response, a series of carbon nanoring isomers with distinct connection patterns between the 2,2'-bipyridine unit and cycloparaphenylene were systematically designed using density functional theory (DFT). Further the sodium (Na) doping generated three distinct isomeric structures: Na@[8]CPPy-1, Na@[8]CPPy-2, and Na@[8]CPPy-2'. Detailed analysis reveals that the Na@[8]CPPy-2 configuration exhibits the largest absolute value of interaction energy, this enhanced stability is primarily attributed to the combined contributions of electrostatic and orbital interactions. Notably, Na incorporation modulates effectively charge transfer, resulting in a significant enhancement of the NLO response. Interestingly, the first hyperpolarizability (βtot) differs among three configurations, with Na@[8]CPPy-2' exhibiting the highest βtot value of 3.51 × 104 au. Simulated UV-Vis absorption spectra reveal that the Na incorporation induces an obvious red shift, indicating that the electronic excitation properties were effectively modulated. Elucidating the influence of metal doping and structural isomerism on NLO properties provides new theoretical insights for designing high-performance carbon-based NLO materials.
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