Three polymers based on pyridine-2,3,5,6-tetracarboxylic acid: Syntheses, crystal structures and luminescent properties

► Three polymers with H4pdtc have been synthesized and characterized. 1 is the first Zn/Mn/K heterotrimetallic complex. ► The H4pdtc molecules show 7-coordinated modes in 1-2 and a 5-coordinated mode in 3. ► Strong photo-luminescent characteristics exhibit in 1-3 in aqueous solution at room temperature.