CRYSTAL-STRUCTURE AND MAGNETIC-PROPERTIES OF COMPLEX H2O)(MU-IM)CO(NH3)(4)(MU-IM)(H2O)CU(DIEN)](NO3)(5)

The crystal structure and variable temperature magnetic susceptibility of [(dien)Cu(H2O) (mu-im)Co(NH3)(4)(mu-im)(H2O)Cu(dien](NO3)(5)(1)) h ave been determined. The complex crystallizes in the monoclinic system . In the cation, the imidazolate ligands connect one Co(III) and two C u(II) atoms, forming an imidazolates-bridged heterotrinuclear complex. Co(III) atom is of a regular octahedral configuration and Cu(II) atom s are of distorted square pyramid configuration. The cations are conne cted by hydrogen bonds through NO3- anions forming infinite chains. Th e fit to magnetic susceptibility data for powder sample over temperatu re range 1.8-300 K shows that there is a weak antiferromagnetic exchan ge interaction between Cu(II) ions in cation. The exchange mechanism h as been discussed.