Single‐molecule Magnet Properties of Silole‐ and Stannole‐ligated Erbium Cyclo‐octatetraenyl Sandwich Complexes
Year: 2025
Type: article
Abstract: The synthesis, structures and magnetic properties of an η5‐silole complex and an η5‐stannole complex of erbium are reported. The sandwich complex anions [(η5‐CpSi)Er(η8‐COT)]– and [(η5‐CpSn)Er(η8‐COT)]–, where CpSi is [SiC4‐2,5‐(SiMe3)2‐3,4‐Ph2]2– (1Si), CpSn is [SnC4‐2,5‐(SiMe3)2‐3,4‐Me2]2– (1Sn) and COT=cyclo‐octatetraenyl, were obtained as their [K(2.2.2‐cryptand)]+ salts and found to be isostructural, with remarkably similar bond lengths and angles, differing only in the lengths of the Er–E interactions (E=Si, Sn). The parallels in the molecular structures of 1Si and 1Sn are reflected in their dynamic magnetic properties, which show single‐molecule magnet behaviour in zero applied field, with effective energy barriers of 115±7 and 125±3 cm–1, respectively, along with comparable magnetic relaxation times. Analysis of the two complexes using ab initio calculations reveals differences at a quantitative level, but overall similar electronic structures, with the thermally activated relaxation likely to proceed via the first‐excited Kramers doublet. Comparing 1Si and 1Sn with the previously reported germanium analogue 1Ge reveals that swapping one heavier group 14 element for another in complexes of the type [(η5‐CpE)Er(η8‐COT)]– has a minimal impact on the SMM behaviour.
Source: Chemistry - A European Journal
Institutions: University of Sussex, Sun Yat-sen University
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,640
OpenAlex ID: W4406869308