Dicarboxylate Modulating Molecular-Ionic Platinum Compounds with Variable Stacking and Photoluminescence.

Under solvothermal conditions, 10 molecular-ionic platinum compounds [Pt(NIA) 2 ]·( L )· n H 2 O ( L = dicarboxylate) were synthesized. In the reaction, acetonitrile undergoes trimerization in situ to generate N -(1-iminoethyl)acetamidine (NIA), which coordinates to Pt II ions in forming the N -(1-iminoethyl)acetamidine platinum cation, while the organic carboxylates act as anions. Structural analysis shows that carboxylate ligands regulate the mode of packing of [Pt(NIA) 2 ] in those compounds. Photoluminescence studies show that the photoluminescence behaviors of those compounds also depended on the carboxylate ligands. 1-4 , 6 , and 7 show blue light emission with fluorescence emission wavelengths of 437-440 nm despite the different carboxylate ligands used. 5 and 8 show green emissions with maximum intensity peak positions of 522 nm. Compared with that of 5 and 8 , the emission of 9 and 10 has the same red shifts with peak positions of 567 and 528 nm. The variable-temperature photoluminescence studies reveal that 8 and 10 show two different thermal quenching (TQ) zones in the range of 80-420 K, while the emission intensity of 9 shows negative thermal quenching at low temperatures of 80-220 K and TQ in the range of 220-420 K.