Syntheses of ferrocene-functionalized indium-based metal–organic frameworks for third order nonlinear optical application

Abstract

We propose a rigid–flexible synergistic strategy for the syntheses of ferrocene-functionalized indium-based metal–organic frameworks (In-MOFs) through introducing rigid carboxylic acids as auxiliary ligands, where the large cations are used to induce flexible 1,1′-ferrocene dicarboxylic acid (H₂FcDCA) in a controllable coordination mode to construct target frameworks. As an illustration of this strategy, a series of In-MOFs based on the H₂FcDCA ligand have been successfully synthesized. The introduction of rigid OX²⁻ ligands and large cation template leads to the syntheses of various In-MOFs. Furthermore, introducing functional cations and a ferrocene unit endows them with good third order nonlinear optical properties and redox activity.