Alkali Metal Doping for Enhancement of Nonlinear Optical Properties of Dicyclopenta[4,3,2,1-ghi:4′,3′,2′,1′-pqr]perylene: A New Bowl-Shaped Fragment of Fullerene C70

Abstract

The electronic properties and the first static hyperpolarizability of a new bowl-shaped of C70 fullerene, the dicyclopenta[4,3,2,1-ghi:4′,3′,2′,1′-pqr]perylene (2CP-Per = C22H10) doped with alkali metals (Li, Na and K) have been investigated employing the density functional theory. Six stable conformations are obtained for Li@2CP-Per, whereas five and four stable structures are formed for Na@2CP-Per and K@2CP-Per, respectively. The nonlinear optical properties of these structures are remarkably to interaction with the type of alkali metals and their relative location at the curved surface of 2CP-Per. The adsorption of Li, Na and K atoms on the surfaces of 2CP-Per narrows the HOMO–LUMO gap of the considered structures. Moreover it is observed that the doping with alkali metals enhances the first hyperpolarizability (β0) of 2CP-Per nanobowl. The β0 value of several doped-structures increases to 40 times of pristine 2CP-Per structure.