CONFORMATIONAL FLEXIBILITY OF THE DI(1,3-DIAMINOPROPANE)COPPER(II) CATION .3. STRUCTURE DETERMINATION FOR TRANS-DIAQUABIS(1,3-DIAMINOPROPANE-N,N')COPPER(II) -DI(ORTHO-PHTHALATO-O)BIS(1,3-DIAMINOPROPANE-N,N') CUPRATE(II) MONOHYDRATE AND DFT CALCULATIONS FOR THE TRANS-DIAQUABIS(1,3-DIAMINOPROPANE-N,N')COPPER(II) CATION

The structure of trans-diaquabis(1,3-diaminopropane-N,N')copper(II) ht halato-O)bis(1,3-diaminopropane-N,N')cuprate(II) dihydrate was determi ned by single crystal X-ray diffraction methods. The compound crystall ises in the triclinic system, space group P (1) over bar (No. 2) with a=7.233(2), b=10.187(2), c=12.905(2) Angstrom, alpha=81.70(2), beta=82 .08(2) and gamma=81.03(2)degrees, and V=922.8(3) Angstrom(3). The stru cture consists of cationic and anionic monomeric coordination units an d a crystal water molecule. Both of the coordination units contain a c entrosymmetric [Cu(tn)(2)](2+) moiety (tn=1,3-diaminopropane). In the cationic unit the axial sites are occupied by water molecules, whereas in the anionic unit there are doubly deprotonated ortho-phthalate ani ons in the axial positions. The respective Cu-O bond lengths are quite long, 2.618(2) and 2.622(2) Angstrom. The six-membered chelate rings formed by the Cu-II ion and tn display a chair conformation. In the an ionic complex unit the rings are less puckered. The geometry of the ca tionic species was optimised by DFT methods and it was found to be mor e stable than a five-coordinated species with a non-coordinated water by 77.4 kJ mol(-1).