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Assisted Self-Assembly to Target Heterometallic Mn-Nd and Mn-Sm SMMs: Synthesis and Magnetic Characterisation of [Mn₇ Ln₃ (O)₄ (OH)₄ (mdea)₃ (piv)₉ (NO₃ )₃ ] (Ln=Nd, Sm, Eu, Gd)*.

ABSTRACT: In an assisted self-assembly approach starting from the [Mn₆ O₂ (piv)₁₀ (4-Me-py)₂ (pivH)₂ ] cluster a family of Mn-Ln compounds (Ln=Pr-Yb) was synthesised. The reaction of [Mn₆ O₂ (piv)₁₀ (4-Me-py)₂ (pivH)₂ ] (1) with N-methyldiethanolamine (mdeaH₂ ) and Ln(NO₃ )₃ ⋅ 6H₂ O in MeCN generally yields two main structure types: for Ln=Tb-Yb a previously reported Mn₅ Ln₄ motif is obtained, whereas for Ln=Pr-Eu a series of Mn₇ Ln₃ clusters is obtained. Within this series the Gd^III analogue represents a special case because it shows both structural types as well as a third Mn₂ Ln₂ inverse butterfly motif. Variation in reaction conditions allows access to different structure types across the whole series. This prompts further studies into the reaction mechanism of this cluster assisted self-assembly approach. For the Mn₇ Ln₃ analogues reported here variable-temperature magnetic susceptibility measurements suggest that antiferromagnetic interactions between the spin carriers are dominant. Compounds incorporating Ln=Nd^III (2), Sm^III (3) and Gd^III (5) display SMM behaviour. The slow relaxation of the magnetisation for these compounds was confirmed by ac measurements above 1.8 K.

SUBMITTER: Kaemmerer H

PROVIDER: S-EPMC8596590 | biostudies-literature |

REPOSITORIES: biostudies-literature

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