75488 20200117221614.0 doi 10.1039/c8dt00685g sideral 108043 ART-2018-108043 eng Fraser, H.W.L. Order in disorder: Solution and solid-state studies of [M III 2 M II 5] wheels (MIII = Cr, Al; MII = Ni, Zn) 2018 Access copy available to the general public Unrestricted A family of heterometallic Anderson-type ''wheels'' of general formula [MIII2MII5(hmp)12](ClO4)4 (where MIII = Cr or Al and MII = Ni or Zn giving [Cr2Ni5] (1), [Cr2Zn5] (2), [Al2Ni5] (3) and [Al2Zn5] (4); hmpH = 2-pyridinemethanol) have been synthesised solvothermally. The metallic skeleton common to all structures describes a centred hexagon with the MIII sites disordered around the outer wheel. The structural disorder has been characterised via single crystal X-ray crystallography, 1-3D 1H and 13C solution-state NMR spectroscopy of the diamagnetic analogue (4), and solid-state 27Al MAS NMR spectroscopy of compounds (3) and (4). Alongside ESI mass spectrometry, these techniques show that structure is retained in solution, and that the disorder is present in both the solution and solid-state. Solid-state dc susceptibility and magnetisation measurements on (2) and (3) reveal the Cr-Cr and Ni-Ni exchange interactions to be JCr-Cr = -1 cm-1 and JNi-Ni, r = -5 cm-1, JNi-Ni, c = 10 cm-1. Fixing these values allows us to extract JCr-Ni, r = -1.2 cm-1, JCr-Ni, c = 2.6 cm-1 for (1), the exchange between adjacent Ni and Cr ions on the ring is antiferromagnetic and between Cr ions on the ring and the central Ni ion is ferromagnetic. info:eu-repo/grantAgreement/ES/MINECO-FEDER/MAT2015-68204-R info:eu-repo/semantics/openAccess by http://creativecommons.org/licenses/by/3.0/es/ 4.052 2018 CHEMISTRY, INORGANIC & NUCLEAR 7 / 45 = 0.156 2018 Q1 T1 1.12 2018 Inorganic Chemistry 2018 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Nichol, G.S. Uhrín, D. Nielsen, U.G. (orcid)0000-0002-8028-9064 Evangelisti, M. Universidad de Zaragoza Schnack, J. Brechin, E.K. 2003 395 Universidad de Zaragoza Dpto. Física Materia Condensa. Área Física Materia Condensada 47, 34 (2018), 11834-11842 Dalton Trans. Dalton Transactions 1477-9226 632898 http://zaguan.unizar.es/record/75488/files/texto_completo.pdf Versión publicada 112193 http://zaguan.unizar.es/record/75488/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:75488 articulos driver 2020-01-17-21:49:45 ARTICLE