Metal-organogermanate frameworks built by two kinds of infinite Ge-O chains with high thermostability and luminescent properties

A bifunctional metalloligand with metal-C (Ge-C) bonds, bis(carboxyethylgermanium) sesquioxide (H₂E₂Ge ₂O₃, where E =-CH₂CH₂COO ^-), has been used to make metal-organometallic frameworks (MOMFs) Cd_1.5(E₃Ge₃O₅) (1) and Pb(E ₂Ge₂O₃) (2). In the structures, the inorganic Ge₂O₃cores of the metalloligands polymerize to form two kinds of infinite Ge-O chains, and the organic carboxyls induce the Cd and Pb ions to produce Cd-O and Pb-O chains. Further, the Ge-O chains link the Cd-O/Pb-O chains via-CH₂CH₂-groups to result in two novel MOMFs, showing high thermostability and blue-violet emission.