SYNTHESIS AND CRYSTAL-STRUCTURE OF THE CO MPLEXES NI(PY)(4)F-2.2H(2)OAND CU(PY)(4)F-2.1.33HF.2H(2)O

Single crystals of Ni(py)(4)F-2 . 2H(2)O (1) and Cu(py)(4)F-2 . 1.33 H F . 2 H2O (2) have been synthesized by solving the precipitated metal fluoride hydrates in pyridine. Both compounds are sensitive to air. Th ey crystallize in the monoclinic space group C2/c with lattice paramet ers a = 13.199(2) Angstrom, b = 10.815(2) Angstrom, c = 15.353(2) Angs trom, beta = 108.08(1)degrees for 1 and a = 28.531(6) Angstrom, b = 8. 767(2) Angstrom, c = 17.572(4) Angstrom, beta = 104.43(3)degrees for 2 . Within both structures the metal atoms are coordinated in form of a distorted square bipyramid, In the case of 1 four pyridine nitrogen at oms are in the basal plane and two fluorine atoms in the apical positi ons. Hydrogen bonding via water molecules lead to infinite chains of N i(py)(4)F-2 molecules connected by doubly ridged [F-2(H2O)(2)] ring un its. In 2 two different complex moieties exist. In one complex two H2O molecules are in the inner coordination sphere besides the four pyrid ine rings; these molecules are interconnected by two F- ions, which ma y be par tially substituted by HF2--groups forming infinite chains alo ng [010], In the other, HF2--ions occupy the apical positions of the s quare bipyramid around the copper ion. They are linked to the fluoride ions of the chains by weak hydrogen bonds of water molecules arranged in between. Thus, the formula should be better given as [Cu(py)(4)(H2 O)(2)][CU(py)(4)(HF2)(2)] . F-1.66(HF2)(0.33) . 2 H2O.