How will the benzyne group -C6H4 affect the structure, electronic and optical properties of M3N@C80 (M = Sc, Y)?

The generalized gradient approximation based on density functional theory is used to study the effects of the benzyne group on the M3N@C-80(M = Sc, Y) clusters. The -C6H4 mainly elongate the nearest C-C bonds of M3N@C-80-C6H4 (M = Sc, Y). It is found that thermodynamically the [5,6] benzoadduct for Sc3N@C-80-C6H4 is slightly more stable than the [6,6] benzoadduct whereas the [6,6] benzoadduct is more stable than the [5,6] benzoadduct for Y3N@C-80-C6H4. Comparison of the absorption spectra of the pristine M3N@C-80 (M = Sc, Y), Sc3N@C-80-C6H4, and Y3N@C-80-C6H4 indicates blue and red shifts, respectively. The benzyne group obviously affects the static linear polarizabilities, screening coefficients and first-order hyperpolarizabilities of the M3N@C-80 (M = Sc, Y) molecules. Our study shows that both the embedded metal atoms and the position of the benzyne affect the structure, electronic and optical properties of the M3N@C-80 (M = Sc, Y) molecules. This may help to design the new optic nanomaterials. (C) 2016 Elsevier B.V. All rights reserved.