Controlled Self‐assembly of Gold(I) Complexes by Multiple Kinetic Aggregation States with Nonlinear Optical and Waveguide Properties
Zongshang Li, Ke Xiao, Qingyun Wan, Rui Tang, Kam‐Hung Low, Xiaodong Cui, Chi‐Ming Che
Abstract
Abstract Introduction of multiple kinetic aggregation states (Aggs) into the self‐assembly pathway could bring complexity and flexibility to the self‐assemblies, which is difficult to realize due to the delicate equilibria established among different Aggs bonded by weak noncovalent interactions. Here, we describe a series of chiral and achiral d 10 Au I bis (N‐heterocyclic carbene, NHC) complexes, and the achiral complex could undergo self‐assembly with multiple kinetic Aggs. Generation of multiple kinetic Aggs was realized by applying chiral or achiral seeds exhibiting large differences in elongation temperatures for their respective cooperative self‐assembly processes. We further showed that the chiral Au I self‐assemblies having non‐centrosymmetric packing forms exhibit nonlinear optical response of second harmonic generation (SHG), while the SHG signal is absent in the achiral analogue. The crystalline achiral Au I self‐assemblies could function as optical waveguides with strong emission polarization.