Family of Heterometallic Semicircular Mn^III₂Ln^III₃ Strands

Abstract

A series of heterometallic complexes of formula [Mn^III₂Ln^III₃(bdeaH)₃(bdea)₂(piv)₈]·MeCN, where bdeaH₂ = <i>N</i>-butyldiethanolamine, piv = pivalate, and Ln = Y (<b>1</b>), Tb (<b>2</b>), Dy (<b>3</b>), Ho (<b>4</b>), and Er (<b>5</b>), has been prepared. <b>1</b>−<b>5</b> are isostructural, with the metal centers forming a novel semicircular Ln^III−Mn^III−Ln^III−Mn^III−Ln^III strand. Only <b>2</b> and <b>3</b> exhibit slow relaxation of the magnetization, suggesting that the highly anisotropic Ln^III ions (Tb^III and Dy^III) are essential for an energy barrier to spin reversal.