Iridium containing honeycomb Delafossites by topotactic cation exchange.

We report the structure and magnetic properties of two new iridium-based honeycomb Delafossite compounds, Cu3NaIr2O6 and Cu3LiIr2O6, formed by a topotactic cation exchange reaction. The starting materials Na2IrO3 and Li2IrO3, which are based on layers of IrO6 octahedra in a honeycomb lattice separated by layers of alkali ions, are transformed to the title compounds by a topotactic exchange reaction through heating with CuCl below 450 °C; higher temperature reactions cause decomposition. The new compounds display dramatically different magnetic behavior from their parent compounds - Cu3NaIr2O6 has a ferromagnetic like magnetic transition at 10 K, while Cu3LiIr2O6 retains the antiferromagnetic transition temperature of its parent compound but displays significantly stronger dominance of antiferromagnetic coupling between spins.

Tuning Sodium Ion Conductivity in the Layered Honeycomb Oxide Na(3-x)Sn(2-x)Sb(x)NaO6.

A series of compounds with the composition Na(3-x)Sn(2-x)Sb(x)NaO6 (x = 0.0, 0.2, 0.

Rhombohedral polytypes of the layered honeycomb delafossites with optical brilliance in the visible.

We report the synthesis of the Delafossite honeycomb compounds Cu3Ni2SbO6 and Cu3Co2SbO6 via a copper topotactic reaction from the layered α-NaFeO2-like precursors Na3Ni2SbO6 and Na3Co2SbO6. The low-temperature exchange reaction exclusively produces the rhombahedral 3R polytype subcell, whereas only the hexagonal 2H polytype subcell has been made by conventional synthesis. The thus-synthesized 3R variants are visually striking; they are bright lime-green (Ni variant) and terracotta-orange (Co variant), while both of the conventionally synthesized 2H variants have a burnt-red color.

Structure and magnetic properties of the spin-1/2-based honeycomb NaNi2BiO(6-δ) and its hydrate NaNi2BiO(6-δ)·1.7H2O.

We present the structure and magnetic properties of the honeycomb anhydrate NaNi2BiO6-δ and its monolayer hydrate NaNi2BiO6-δ·1.7H2O, synthesized by deintercalation of the layered α-NaFeO2-type honeycomb compound Na3Ni2BiO6. The anhydrate adopts ABAB-type oxygen packing and a one-layer hexagonal unit cell, whereas the hydrate adopts an oxygen packing sequence based on a three-layer rhombohedral subcell.

Formation of the tetranuclear, tetrakis-terminal-imido Mn4(IV)(N(t)Bu)8 cubane cluster by four-electron reductive elimination of (t)BuN=N(t)Bu. The role of the s-block ion in stabilization of high-oxidation state intermediates.

Mn4(IV)(μ3-N(t)Bu)4(N(t)Bu)4 is obtained from a previously reported asymmetric Mn(IV/V)-Li-(NR)(N) cluster by the removal of Li from the starting cluster by ion metathesis, which triggers reductive elimination of azo-tert-butane to give a tetranuclear heterocubane cluster.