Unprecedented NaI–CuII–LnIII heterometallic coordination polymers based on 3,5-pyrazoledicarboxylate with both infinite cationic and anionic chains

The self-assembly of 3,5-pyrazoledicarboxylic acid (H3pdc) and metal salts under hydrothermal conditions leads to the formation of a series of novel NaI–CuII–LnIII heterometallic coordination polymers, {[Na(H2O)4]2[Cu(pdc)2Ln(H2O)5]2·3H2O}n [Ln = La (1); Sm (2); Pr (3); Nd (4) and pdc3− = 3,5-pyrazoledicarboxylate]. X-Ray structure analyses show that these complexes all exhibit pairs of infinite, unexpected, cationic and anionic chains. It is the first successful attempt to construct unprecedented NaI–CuII–LnIII heterometallic coordination polymers with both infinite cationic and anionic chains. These four complexes show homologous thermal stabilities. The different magnetic properties of 1–3 are also been reported in this paper.