Crystal and molecular structures of dinitrato(1,10-phenanthroline)copper(II) and diaquanitrato(1,10-phenanthroline)copper(II) nitrate

Abstract

The crystal structures of the title compounds. (I)[Cu(C₁₂H₈N₂)(NO₃)₂] and (II)[Cu(C₁₂H₈N₂)(NO₃)(H₂O)₂]-[NO₃], have been determined from three-dimensional X-ray diffractometer data and refined by full-matrix least-squares calculations to R 0.045 [(I), 1 181 reflections] and 0.058 [(II), 1 525 reflections].

Crystals of (I) and (II) are monoclinic, space group P2₁/c, with Z= 4 in cells of dimensions: (I)a= 8.76(1), b= 9.12(1), c= 17.63(1)Å, β= 107.4(1)°; (II)a= 7.03(1), b= 20.20(1), c= 11.49(1)Å. β= 109.9(1)°.

Crystals of (I) contain polymeric Cu(C₁₂H₈N₂)(NO₃)₂ units in which one of the nitrato-groups is terdentate and serves to bridge the units along the 2₁ screw axis. The copper atom is seven co-ordinate: Cu–N(phen) 1.994(5), 2.018(5); Cu–O(NO₃) 1.960(5), 1.996(4), 2.326(4), 2.814(5), and 2.863(5)Å.

In (II) the copper atom is in a distorted octahedral environment with Cu–N(phen) 2.005(6), 2.008(6), Cu–O(NO₃) 1.983(5), and Cu–O(H₂O) 2.005(6)Å defining the basal plane. A second water oxygen [Cu–O 2.261 (6)Å], and an oxygen of the asymmetrically bidentate nitrato-group [Cu–O 2.594(6)Å] occupy the axial sites. The nitrate ion is involved in three hydrogen bonds to the co-ordinated water molecules.