Synthesis of (sub)microcrystals of dinuclear terbium(III) carboxylate (Hpiv)6Tb2(piv)6 and polymeric terbium(III) carboxylate {Tb(piv)3}n in supercritical carbon dioxide. Photoluminescence and magnetic properties

Abstract

Supercritical fluid micronization by rapid expansion of supercritical solutions setup using supercritical carbon dioxide as a fluid and the dinuclear complex (Hpiv)6Tb2(piv)6 (1) as the starting compound allows the preparation of either the single-phase dinuclear complex (Hpiv)6Tb2(piv)6 (1a) or the coordination polymer {Tb(piv)3}n (2a, 2b, 2c) as (sub)microcrystals with a controlled size depending on the processing parameters. It was shown that {Tb(piv)3}n (2) can in principle be synthesized by supercritical carbon dioxide processing as polycrystalline particles with different morphologies. A decrease in the size of polycrystalline particles (aggregates) of 1 and 2 and an increase in the fraction of defects in the crystal structure, respectively, lead to an increase in the degree of photoluminescence quenching at these defects and a change in magnetic properties of 1.