Structural, electronic, and nonlinear optical properties of small silver clusters doped graphyne and pyrazine‐modified graphyne: A computational and comparative study

Abstract The electronic and second‐order nonlinear optical (NLO) properties of small Ag n clusters ( n = 1 to 3) doped graphyne (GY) and pyrazine‐modified graphyne (pyGY) have been investigated employing (time‐dependent) density functional theory calculations. A large triangular hole of GY provides an efficient site to accommodate the Ag n cluster, and an Ag atom prefers to be located in the center of the pyGY, interacting with the two pyridine N atoms. The silver clusters have strong interactions with GY/pyGY, and the intramolecular charge transfer is significant for determining NLO properties. The first hyperpolarizability ( β 0 ) values can be modulated by the introduction of silver clusters. The results show that the second‐order NLO response of Ag 2 /Ag 3 doped pyGY complex is stronger than that of corresponding Ag 2 /Ag 3 doped GY complex, while the β 0 for single Ag doped GY is significantly higher than that of Ag@pyGY. Hence, the NLO responses of these complexes depend on the size of the clusters and the type of nanosheets. All complexes exhibit excellent transparency in the deep ultraviolet region, especially Ag 3 @GY/pyGY. These results suggest that these Ag n clusters doped GY/pyGY are excellent candidates for potential applications in optical devices.