▎ 摘　　要

Recent successful syntheses of azulene-defect graphene nanosheets (GNSs) pave a path for the applications of those GNSs in nonlinear optics, since azulene-defect GNSs maintains the thermal stability of carbon-based nanomaterials and possesses potential large nonlinear optical (NLO) responses. In the present work, azulene-defect GNSs with different relative position and orientation are designed for applications in optoelectronics and nonlinear optics. The all-carbon azulene-defect GNS Paral-2 with parallel orientated azulenes has good electronic kinetic stability as well as a large static first hyperpolarizability () of 1032.28 x 10(-30) esu (18.43 x 10(-30) esu per heavy atom). The Paral-0-4N, formed by replacing four edge C atoms with N atoms in the GNS Paral-0, has the largest (1247.68 x 10(-30) esu, 22.28 x 10(-30) esu per heavy atom) due to the charge transfer based electron excitations and the polar structure while with enhanced electronic kinetic stability. The two-dimensional second order NLO spectra of those azulene-defect GNSs provide vital information for further experimental exploration and applications. The introduction of polar azulene in GNSs to improve the NLO responses and doping of nitrogen atoms to enhance the electronic kinetic stability of GNSs provide a practical strategy and useful information for future NLO materials design.