Structures of 1,1′,3,3′-Tetra(2-methyl-2-nonyl)ferrocenium(1+) Oxoanion(1−) Salts. Layered Materials with Alternating Ionic and Low-Dielectric Paraffin-Like Domains Through Which Anion Diffusion is Rapid

Abstract

The unprecedented interdigitated and layered structures of 1,1′,3,3′-tetra­(2-methyl-2-nonyl)­ferrocene (DEC) and the oxoanion ferrocenium salts DEC+NO3 –, DEC+ClO4 –, and DEC+ReO4 – were determined by single-crystal X-ray diffraction. The four structures are similar except that the three DEC+ salts have layers of XO n – oxoanions stuffed between the layers of interdigitated ferrocenium ions. The perpendicular distances between layers of Fe atoms are 8.530, 9.108, 9.009, and 9.158 Å for DEC, DEC+NO3 –, DEC+ClO4 –, and DEC+ReO4 –, respectively. The structures also contain layers of rigorously coplanar Fe and X atoms that are tilted 65.4, 75.9, 61.9, and 61.1° from the aforementioned layers of Fe atoms for DEC, DEC+NO3 –, DEC+ClO4 –, and DEC+ReO4 –, respectively. The local environments of the XO n – oxoanions consist of networks of C–H···O hydrogen bonds, and the structures exhibit channels through which these anions could diffuse. Facile diffusion of these anions in thin films of DEC+XO n –, with structures that appear to resemble the crystal structures, has been demonstrated.

X-ray structures and electronic properties of the 1,1′,2,2′- and 1,1′,3,3′-tetra-t-butylferrocenium(1+) cations

“…Re-O angles with those in the two new structures is not meaningful[21]. Note that there are two independent but nearly identical cations and anions in the structure of[1,2-BUT + ][ReO 4 − ].…”