Copper Keplerates: High‐Symmetry Magnetic Molecules

Abstract

Keplerates are molecules that contain metal polyhedra that describe both Platonic and Archimedean solids; new copper keplerates are reported, with physical studies indicating that even where very high molecular symmetry is found, the low‐temperature physics does not necessarily reflect this symmetry.

Breaking the Gordian Knot in the Structural Chemistry of Polyoxometalates: Copper(II)–Oxo/Hydroxo Clusters

“…So far the host–guest [X@Cu II 12 (OH) 24 ] q − assemblies have been obtained with M cations, such as Mg II , Ca II , Cu II , Zn II La III , Gd III , or Dy III . It is interesting to note that the alkaline earth metal and the transition metal dications readily participate in the formation of [X q @M m 8 Cu II 12 (OH) 24 ] 8 m − q structures, while as presented in the next section, only lanthanide trications have been reported so far to participate in the formation of [X q @M m 6 Cu II 12 (OH) 24 ] 6 m − q structures.…”

“…These compounds were synthesized by reacting Ln(NO 3 ) 3 ⋅ x H 2 O (Ln=Gd III or Dy III ), Cu(OOCMe) 2 ⋅H 2 O, and TPAH 2 in acetonitrile followed by addition of bases LiOMe or Me 4 NOH/Et 3 N. Notably, the dysprosium derivative shows SMM behavior. A magnesium‐related polycation [H 2 O@Mg 8 Cu 12 (OH) 24 (MeCOO) 12 (H 2 O) 12 ] 4+ , obtained by reaction of Cu(NO 3 ) 2 ⋅6 H 2 O, Mg(NO 3 ) 2 ⋅6 H 2 O, and NaOOCMe in methanol, has also been described . A reaction at room temperature between a solution of [Cu 2 ( t BuCOO) 4 ( t BuCOOH) 2 ] in acetonitrile and an aqueous solution of i PrNH 2 and NEt 3 resulted in a compound the structure of which incorporates two motifs formally written as [(NH 2 i Pr)@Cu 20 (OH) 24 (NH 2 i Pr) 6 ] 16+ and [(NH 2 i Pr)@Cu 20 (OH) 24 ( t BuCOO) 8 (OH) 4 (NH 2 i Pr) 6 ] 4+ …”

Royal Society of Chemistry Prizes and Awards 2016

“…Winpenny and his group are interested in molecular magnetism and, more broadly, nanoscience, including supramolecular assemblies of molecular magnets and the magnetism of lanthanide complexes. He has reported in ChemPhysChem on copper keplerates …”

Auszeichnungen der Royal Society of Chemistry 2016

“…B. supramolekulare Assoziate molekularer Magnete und der Magnetismus von Lanthanoidkomplexen. In ChemPhysChem hat er Kupferkeplerate vorgestellt …”