Coordinative Capability of Propane-1,3-diamine: Spectroscopic and Structural Properties of a Complex of Formula [Cd(pnH)4Cl2]Cl4

The compound [Cd(pnH)4Cl2]Cl4 (pn=propane-l,3-diamine) has been prepared and studied by means of spectroscopic (IR and Raman) and structural investigations. It crystallizes in the tetragonal P4nc space group (No. 104), with two formula units in a cell of dimensions: a=b=ll.972(4), c=9.129(4) Å. The structure consists of an ionic packing of chlorine anions and of discrete [Cd(pnH)4Cl2]4+ cations; the Cd atoms are octahedrally coordinated to four nitrogen atoms of four distinct monoprotonated diamines and to two chlorine atoms in trans position to each other, showing very loose CdCl bonding interactions (2.680(3) and 2.884(2) Å). The protonated ends of the propane-l,3-diamines interact with the non-coordinated chlorine ions via hydrogen bonding. The CdN and CdX stretching vibrations are discussed and assigned in the light of the known structures.