The current study has obtained excellent potential nonlinear optical(NLO)materials by combining density functional theory methods with sum-over-states model to predict the second order NLO properties of helical graphene nanoribbons(HGNs)through introducing azulene defects or/and BN units.The introduc-tion of these functional groups deforms the pristine HGN(compression or tension)and enhances obviously the static first hyperpolarizability(<β0>)of system by up to two orders of magni-tude.The tensor components along the helical axis of HGNs play a dominant role in the total<β0>.The azulene defects and the BN units polarize the pristine HGN to different degrees,and the azulenes and contiguous benzenes are involved in the major elec-tron excitations with significant contributions to<β0>but the BN units are not.The BN-doped chiral HGNs have good kinetic stability and strong second order NLO properties(6.84×105×10-30 esu),and can be a potential candidate of high-performance second order NLO materials.The predicted two-dimensional second order NLO spectra provide useful information forfurther exploration of those helicenes for electro-optic applications.

ZHENG Xuelian;LIU Lingi;YANG Cuicui;HE Yuanyuan;CHEN Jiu;TIAN Wei Quan

Chongqing Key Laboratory of Theoretical and Computational Chemistry,College of Chemistry and Chemical Engineering,Chongqing University,Chongqing 401331,P.R.China;Department of Materials Science and Engineering,Southern University of Science and Technology,Shenzhen 518055,P.R.China

高等学校化学研究（英文版）

[1]ZHENG Xuelian;LIU Lingi;YANG Cuicui;HE Yuanyuan;CHEN Jiu;TIAN Wei Quan-.Modulation of the Second Order Nonlinear Optical Properties of Helical Graphene Nanoribbons Through Introducing Azulene Defects or/and BN Units)[J].高等学校化学研究（英文版）,2022(04):974-984

Nanoribbons,Azulene,HGNs,azulene,hyperpolarizability,magni,azulenes,forfurther,helicenes

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