To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nido...To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nidocarboranes and alkynes directly afford two distinct types of 2D-3D fused carboranyl polycyclic compounds:3a-3f,4a-4d.The structures of this series of compounds were characterized by nuclear magnetic resonance spectroscopy,single-crystal X-ray diffraction,and high-resolution mass spectrometry,and a plausible reaction mechanism was proposed.Crystal structures reveal that the multiple rings in such 2D-3D fused carboranyl polycyclic compounds exhibit a certain degree of coplanarity.Furthermore,these compounds exhibited properties distinct from those of conventional 2D polycyclic systems.CCDC:2481988,3c,2481990,3f,2481986,4d.展开更多
We numerically investigate the effect of in-plane bending strain on valley-resolved conductance and valley polarization in a graphene nanoribbon with zigzag edges.The central region of the nanoribbon is bent into an a...We numerically investigate the effect of in-plane bending strain on valley-resolved conductance and valley polarization in a graphene nanoribbon with zigzag edges.The central region of the nanoribbon is bent into an arc with central angleφ.We find that the bending strain reduces the conductance but enhances the valley polarization.In the valley-resolved conductance spectra,there exist single-valley plateaus near the Dirac points and distinct Fano-type dips.Accordingly,a plateau of full valley polarization appears,which expands significantly at largeφ.At valleyresolved conductance dips,the valley polarization can be much larger than that in the unstrained case.The bending-induced enhancement of valley polarization can be explained by the features of pseudo-Landau levels in the bent region.Strain-induced valley polarization depends nonmonotonously on the nanoribbon width.These findings could be helpful in designing valleytronic devices with flexibility.展开更多
文摘To address the longstanding challenge in traditional carborane methodology of rapidly and efficiently constructing carboranyl-based polycyclic frameworks,Pd-catalyzed one-pot reactions between pyridyl-substituted nidocarboranes and alkynes directly afford two distinct types of 2D-3D fused carboranyl polycyclic compounds:3a-3f,4a-4d.The structures of this series of compounds were characterized by nuclear magnetic resonance spectroscopy,single-crystal X-ray diffraction,and high-resolution mass spectrometry,and a plausible reaction mechanism was proposed.Crystal structures reveal that the multiple rings in such 2D-3D fused carboranyl polycyclic compounds exhibit a certain degree of coplanarity.Furthermore,these compounds exhibited properties distinct from those of conventional 2D polycyclic systems.CCDC:2481988,3c,2481990,3f,2481986,4d.
基金supported by the public welfare project(Normal Education Quality Improvement Plan)by the China Education Development Foundation(Grant No.TZJH202202)the National Natural Science Foundation of China(Grant No.12274370)。
文摘We numerically investigate the effect of in-plane bending strain on valley-resolved conductance and valley polarization in a graphene nanoribbon with zigzag edges.The central region of the nanoribbon is bent into an arc with central angleφ.We find that the bending strain reduces the conductance but enhances the valley polarization.In the valley-resolved conductance spectra,there exist single-valley plateaus near the Dirac points and distinct Fano-type dips.Accordingly,a plateau of full valley polarization appears,which expands significantly at largeφ.At valleyresolved conductance dips,the valley polarization can be much larger than that in the unstrained case.The bending-induced enhancement of valley polarization can be explained by the features of pseudo-Landau levels in the bent region.Strain-induced valley polarization depends nonmonotonously on the nanoribbon width.These findings could be helpful in designing valleytronic devices with flexibility.
