Utilizing Planar σ-Aromaticity to Enhance Electron Transport Abilities
In organic chemistry,aromaticity is a fundamental concept.The aromaticity of traditional aromatic compounds usually comes from the high delocalization of π-electrons on the upper and lower planes of the ring,while σ-aromaticity mainly comes from the intramolecular σ bond and orbital overlap,both of which can affect the electron transport capacity of the molecule.In this study,density functional theory combined with non-equilibrium Green's function(DFT+NEGF)meth-od are used to systematically investigate the aromaticity and electronic transport properties of benzene,thiophene,furan,and their derivatives.The computational results reveal that both π-aromaticity and σ-aromaticity have pronounced effects on mo-lecular electronic transport,where σ-aromaticity shows a positive correlation with electron transmission,whereasπ-aromaticity displays a negative correlation.The charge transfer properties of diphenyl dithiol(DB),dithiophene dithiol(DT)and difuran dithiol(DF)molecules containing two aromatic rings are significantly influenced by molecular planariza-tion.Moreover,the furan ring in DF exhibits a larger NICS(1)zz value than the thiophene ring in DT.Furthermore,aromatic compounds typically exhibit a better coplanar trend.The molecular design strategy involving the modification of DT and DF molecules with F atom generates intramolecular F…S and F…O non-covalent interactions,which significantly enhance mo-lecular planarity and rigidity.Meanwhile,the virtual five-membered ring structures containing intramolecular F… S and F…O interactions have σ-aromaticity characteristics,effectively promoting electron transport along F…S and F…O pathways,thereby improving the electron transport capacity.This research contributes to further understanding of the intrinsic relation-ship between molecular aromaticity and electronic transport capacity,and provides strategies for designing more efficient electronic devices in the future.
NETL
NSTL
万方数据
