Core-Shell {Mn7⊂(Mn,Cd)12} Assembled from Core {Mn7} Disc

Abstract

Postsynthetic decoration of the Mn₇, {Mn^III⊂Mn^II₆}, core with Cd^II in the outer shell to form the next generation Mn₁₃Cd₆, {Mn^III⊂Mn^III₃Mn^II₃⊂ Mn^II₆Cd^II₆}, core-shell disc was achieved and confirmed by single-crystal X-ray diffraction. The formation of Mn₁₃Cd₆ has only been successful with Cd^II and if the Cd salt is added within the first half hour window when the inner Mn₇ has formed. EDX and ICP-AES gave the accurate content and confirm the average found by X-ray diffraction. HR-ESI-MS was even more precise by revealing three prominent molecular species, Mn₁₃Cd₆, Mn₁₄Cd₅ and Mn₁₅Cd₄, having a distribution of metals. The presence of nonmagnetic metal on the periphery reduces the exchange between these clusters as well as the low magnetic moment decreases the dipolar interaction resulting in a paramagnet compared to the ferrimagnetism found for the parent Mn₁₉, {Mn^III⊂Mn^III₃Mn^II₃⊂Mn^II₁₂}, disc. This study opens the way for the syntheses of heterometallic core-shell clusters in a controllable fashion.