Roentgenostructural investigation of crystals of nitrosodicyanmethanide bis-(nitrosodicyanmethanido)-tetrakis-[tris-(dimethylamino) phosphineoxide] of ytterbium(3), [Yb[ONC(CNΛ2)]Λ2 [OP[N(CHΛ3)Λ2]Λ3]Λ4]ONC(CN)Λ2

Using the method of X-ray structural analysis (diffractometer, MoKsub(α)-radiation, 4396 reflections, iso-anisotropic least square Method in a full matrix variant up to R=0.081). The crystal structure of [Yb[ONC(CN2)x(OP[N(CH3)2]3)4]ONCx(CN)2 has been determined. Parameters of monoclinic cell are as folloWs: a=11.440 (3), b=14.728(3), c=34.912(9) A, β=97.53(2deg, V=5832(3) A3, dsub((measured picnometrically))=1.30 (1), dsub((calculated roentgenographically))=1.335 g/cm3, Z=4, sp.gr. P21/c. Complex cation [Yb[ONC(CN)2)2x(OP[N(CH3)2]3)4]+ and second sphere ONC(CN)2-group, occupying statistically two positions, are structural elements of the crystals. Coordination number of ytterbium is 6 (all the ligands are coordinated in a monodentate way by means of oxygen atom), coordination polyhedron-asymmetrically extended tetragonal bipyramid, apical vertices of which are occupied by oxygen atoms of acide ligands. Average bond length Yb-O(OP[N(CH3)2]3) constitutes 2.197(11)A. Distances from Yb to oxygen of ONC(CN)2-groups equal 2.233(15) and 2.315(18)A. The presence of inversion pseudoaxis of the fourth order is a characteristic feature of the complex cation. The structure of the coordination polyhedron, phosphoryl and nitrosodicyanmethanide ligands is discussed, using literature data