| Autor: |
Fraser HWL; EaStCHEM School of Chemistry, The University of Edinburgh, David Brewster Road, Edinburgh, EH9 3FJ Scotland, UK. E.Brechin@ed.ac.uk., Nichol GS, Baldansuren A, McInnes EJL, Brechin EK |
| Jazyk: |
angličtina |
| Zdroj: |
Dalton transactions (Cambridge, England : 2003) [Dalton Trans] 2018 Nov 21; Vol. 47 (43), pp. 15530-15537. Date of Electronic Publication: 2018 Oct 19. |
| DOI: |
10.1039/c8dt03793k |
| Abstrakt: |
A family of heterometallic Anderson-type 'wheels' of general formula [MM(hmp) 12 ] 4+ (M III = Cr or Al and M II = Ni or Zn, Hhmp = 2-pyridinemethanol) has been extended to include M III = Cr or Al and M II = Co, Fe, Mn or Cu, affording five new species of formulae [Cr 2 Co 5 (hmp) 12 ](ClO 4 ) 4 (1), [Cr 2 Fe 5 (hmp) 12 ](ClO 4 ) 4 (2), [Cr 2 Mn 5 (hmp) 12 ](ClO 4 ) 4 (3), [Cr 2 Cu 5 (hmp) 12 ](ClO 4 ) 2 (NO 3 ) 2 (4) and [Al 2 Co 5 (hmp) 12 ](ClO 4 ) 4 (5). As per previous family members, the metallic skeleton common to the cations of 1-5 describes a centred hexagon with the two M III sites disordered around the outer wheel, with the exception of compound 4 where the Cu II sites are localised. A structurally related, but enlarged planar disc possessing a [MM II ] hexagon capped on each edge by a Cu II ion can be formed, but only when M III = Al and M II = Cu. In [AlCu(OH) 12 (hmp) 12 ](ClO 4 ) 6 (NO 3 ) 2 (6) the Anderson moiety contains a central, symmetry-imposed octahedral Cu II ion surrounded by a wheel of Al III ions. Solid-state dc susceptibility and magnetisation measurements reveal the presence of competing exchange interactions in 1-5, and very weak antiferromagnetic exchange between the Cu II ions in 6 which may be intra- and/or intermolecular in nature. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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