NEW THREE DIMENSIONAL [Cd(CN)2]n FRAMEWORK FORMED WITH CADMIUM CYANIDE AND Cd(CN)2·(18-CROWN-6): CRYSTAL STRUCTURE OF [Cd(CN)2]·1/2[Cd(CN)2 (18-CROWN-6)]·3/2EtOH
Titel:
NEW THREE DIMENSIONAL [Cd(CN)2]n FRAMEWORK FORMED WITH CADMIUM CYANIDE AND Cd(CN)2·(18-CROWN-6): CRYSTAL STRUCTURE OF [Cd(CN)2]·1/2[Cd(CN)2 (18-CROWN-6)]·3/2EtOH
Auteur:
Kim, Jaheon Kim, Kimoon
Verschenen in:
Journal of coordination chemistry
Paginering:
Jaargang 37 (1996) nr. 1-4 pagina's 7-15
Jaar:
1996-02-01
Inhoud:
The cadmium complex Cd(CN)2·(18-crown-6) (1) was synthesized and its structure was determined by X-ray crystallography. The cadmium ion in 1 has a hexagonal bipyramidal geometry containing six equatorial oxygen atoms from the crown ether and two axial CN ligands. The NC-Cd-CN 'rod' is perfectly linear with an end-to-end distance of 6.509 (12) Å. When 1 was allowed to diffuse into a cadmium cyanide solution, the infinite coordination complex [Cd(CN)2]·1/2[(Cd(CN)2·(18-crown-6)]·3/2EtOH (2) was obtained in which the cadmium macrocycle 1 was trapped in a 10-faced-cage formed by the [Cd(CN)2]n framework. The terminal nitrogen atoms of 1 bind two Cd centers across the cage. The trapped Cd(CN)2·(18-crown-6) has a significantly bent NC-Cd-CN unit and the crown ether ligand disordered over two orientations. The [Cd(CN)2]n framework viewed down the c axis shows two types of channels, one octagonal and one tetragonal, which are filled with Cd(CN)2·(18-crown-6) and ethanol molecules, respectively. Crystallographic data of 1: trigonal, space group R·3 (hexagonal axis), a = 11.757 (1), c = 12.105 (1) Å, V = 1449.1 (2) Å3, Z = 3, R = 0.0566, Rw = 0.0674 for 827 unique reflections (I>3σ(I)). Crystallographic data of 2: orthorhombic, Pbcn, a = 16.632 (1), b = 17.391 (3), c = 15.685 (2) Å, V = 4536.8 (9) Å3, Z = 8. R = 0.0486, Rw = 0.0492 for 929 unique reflections (I>3σ(I)).