Crystal structure of catena-poly[[gold(I)-μ-cyanido-[di-aqua-bis-(2-phenyl-pyrazine)-iron(II)]-μ-cyanido] dicyanidogold(I)

Olesia I Kucheriv,Sergiu Shova,Il'Ya A Gural'Skiy,Sergey O Malinkin,Diana D Barakhtii

doi:10.1107/s2056989019009678

Abstract

In the title polymeric complex, {[Fe(CN)2(C10H8N2)2(H2O)2][Au(CN)2]} n , the FeII ion, which is located on a twofold rotation axis, has a slightly distorted FeN4O2 octa-hedral geometry. It is coordinated by two phenyl-pyrazine mol-ecules, two water mol-ecules and two di-cyano-aurate anions, the Au atom also being located on a second twofold rotation axis. In the crystal, the coordinated di-cyano-aurate anions bridge the FeII ions to form polymeric chains propagating along the b-axis direction. In the crystal, the chains are linked by Owater-H⋯Ndi-cyano-aurate anions hydrogen bonds and aurophillic inter-actions [Au⋯Au = 3.5661 (3) Å], forming layers parallel to the bc plane. The layers are linked by offset π-π stacking inter-actions [inter-centroid distance = 3.643 (3) Å], forming a supra-molecular metal-organic framework.

Highlights

In the title polymeric complex, {[Fe(CN)2(C10H8N2)2(H2O)2][Au(CN)2]}n, the FeII ion, which is located on a twofold rotation axis, has a slightly distorted FeN4O2 octahedral geometry
It is coordinated by two phenylpyrazine molecules, two water molecules and two dicyanoaurate anions, the Au atom being located on a second twofold rotation axis
The chains are linked by Owater—HÁ Á ÁNdicyanoaurate anions hydrogen bonds and aurophillic interactions [AuÁ Á ÁAu = 3.5661 (3) A ], forming layers parallel to the bc plane

Summary

Chemical context

The design of functional materials based on coordination compounds is an important area of current scientific research. Fe-based coordination polymers with N-donor bridging ligands are well known as compounds with switchable spin states (Niel et al, 2003; Gural’skiy et al, 2016; Kucheriv et al, 2016). This phenomenon is called spin crossover and can be observed in complexes of 3d4–3d7 metal ions. The synthesis and crystallographic characterization of these complexes are of current interest because of the bistability of their magnetic, electrical, mechanical and optical properties (Senthil Kumar & Ruben, 2017) The parameters of these transitions could be controlled through a wide variety of available organic ligands and co-ligands. Symmetry codes: (i) x; y À 1; z; (ii) Àx þ 1; Ày þ 1; Àz þ 1; (iii) Àx þ 1; y; Àz þ 32; (iv) x; y þ 1; z

Structural commentary

Supramolecular features

Database survey

Synthesis and crystallization

Refinement