AN EXPLORATION OF STRUCTURALLY CHARACTERIZED HETERO-TRINUCLEAR [Cu(II)2Ca(II)] FLEXIBLE-BIS(SALAMO)-TYPE COMPLEX

A new bis(salamo)-type ligand has been designed and synthesized, and its hetero-trinuclear [Cu(II)2Ca(II)] complex has been successfully prepared. It is characterized by elemental analyses, IR spectra, UV-Vis absorption spectra and X-ray single crystal diffraction. Meanwhile, Hirshfeld surfaces and fluorescence properties were investigated. The hetero-trinuclear [Cu(II)2Ca(II)] complex was obtained by 2 equiv. Cu(NO3)2·3H2O and 1 equiv. Ca(OAc)2·2H2O with 1 equiv. H4L. Obviously, there is the ligand, metal Cu(II) and Ca(II) ratio of 1:2:1 which formed the hetero-trinuclear [Cu(II)2Ca(II)] complex. X-ray diffraction result showed that Cu(II) and Ca(II) atoms in the crystal are geometric polyhedrons with different shapes. Both Cu(II) atoms are located respectively in N2O2 cavities of the completely deprotonated ligand (L)4– unit. Cu(II) and Ca(II) atoms are bridged by nitrate groups, so that the two Cu(II) (Cu1 and Cu2) atoms have slightly distorted square pyramid geometries. In addition, Ca(II) atom is located in a O6 cavity of the ligand (L)4– unit and possesses square antiprism with eight coordination.