Syntheses, Structures, and Photoluminescent Properties of Three Silver(I) Cluster-Based Coordination Polymers with Heteroaryldicarboxylate

Three silver(I) cluster-based coordination polymers, namely, [Ag 3 (podc)(H 2 O) 2 ]·2H 2 O ( 1 ), [Ag 2 (pidc)] ( 2 ), and [Ag 2 (pidc)(H 2 O)] ( 3 ) (H 3 podc = 3,5-pyrazoledicarboylic acid and H 2 pidc = 2,3-pyrazinedicarboxylic acid) have been synthesized. Among them, 1 consists of stairlike one-dimensional chains with boxlike units as well as the zigzag tetranuclear silver(I) cluster subunits [Ag···Ag 2.778(1) and 3.230(1) Å]; 2 features new parallel single-strand silver(I) helices that propagate by the 4 1 -screw symmetry with short Ag···Ag contacts [Ag2···Ag2 3.158(1) Å] along the c -axis and display the same handedness, while 3 features hexagonal Ag 4 (μ 2 -O) 2 cores, in which the Ag···Ag separation is 3.150(2) Å. These complexes display room temperature photoluminescence in the blue/green region, which may be assigned to an admixture of ligand-to-metal charge transfer and metal-centered (d−s/d−p) transitions.