Hydrate Isomerism in Coordination Polymers of Bismuth and Acetylenedicarboxylate

Single crystals of $\rm^{2}_{\infty}$ [Bi(ADC) 2/4 (ADC) 3/3 (H 2 O) 2 ] · 2H 2 O ( P $\bar{1}$ , Z = 2) and $\rm^{3}_{\infty}$ [Bi(ADC) 2/4 (ADC) 3/3 (H 2 O) 3 ] · H 2 O ( P $\bar{1}$ , Z = 2) were obtained by isothermal evaporation of aqueous solutions containing acetylenedicarboxylic acid (H 2 ADC) and Bi(NO 3 ) 3 · 5H 2 O. Their crystal structures were solved and refined from X‐ray single crystal data. They are hydrate isomers with respect to the central Bi 3+ ion, which leads to completely different topologies of the resulting coordination polymers.