Crystal structures of tris(1,8-naphthyridine)(perchlorato)mercury(II) perchlorate and tetrakis(1,8-naphthyridine)cadmium(II) bis(perchlorate)

Abstract

The crystal structures of the title compounds, (I)[Hg(N₂C₈H₆)₃(ClO₄)][ClO₄] and (II)[Cd(N₂C₈H₆)₄][ClO₄]₂, have been determined from single-crystal diffractometer data and refined to R 0·08 [(I) 2595 reflections] and 0·07 [(II) 1147 reflections].

Crystals of (I) are triclinic, space group P, a= 11·786(3), b= 13·480(3), c= 9·820(1)Å, α= 103·98(1), β= 111·81 (1), γ= 77·44(2)°, Z= 2. Crystals of (II) are triclinic, space group P, a= 9·273(1), b= 9·496(1), c= 20·001(3)Å, α= 99·01 (1), β= 79·49(1), γ= 90·95(1)°, Z= 2.

In (I), the mercury atom is involved in an irregular seven-co-ordination with the three asymmetrically co-ordinated bidentate ligands and one of the perchlorate oxygen atoms. [Hg–N: 2·64, 2·30; 2·84, 2·14; 2·87, 2·20(2); Hg–O, 2·93(4)Å.]

(II) Is isostructural with the corresponding iron(II) derivative, the metal atom being eight-co-ordinate [Cd–N: 2·44, 2·47; 2·44, 2·57; 2·59, 2·42; 2·39, 2·73(2)Å]. The thermal motion of the perchlorate atoms in both structures is high but there appears to be no disorder.