Pentanuclear complexes with unusual structural topologies from the initial use of two aliphatic amino-alcohol ligands in Fe chemistry
Φόρτωση...
Ημερομηνία
Συγγραφείς
Kizas, C. M.
Manos, M. J.
Nastopoulos, V.
Boudalis, A. K.
Sanakis, Y.
Tasiopoulos, A. J.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Royal Society of Chemistry
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Dalton Transactions
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
Five novel pentanuclear Fe3+ clusters with the aliphatic amino-alcohol ligands 3-amino-1-propanol (Hap) and 2-(hydroxymethyl)piperidine (Hhmpip) [Fe-5(mu(3)-O)(2)(L)(4)(O2CR)(7)] [L = ap(-), R = Ph (1); L = ap(-), R = C(CH3)(3) (2); L = hmpip(-), R = Ph (3); L = hmpip(-), R = C(CH3)(3) (4)] and [Fe-5(mu(4)-O)(mu(3)-O)-(O2CC(CH3)(3))(8)(ap)(2)Cl(HO2CC(CH3)(3))] (5) are reported. Compounds 1-4 were prepared from reactions of preformed trinuclear Fe3+ clusters with the ligands in a molar ratio 1 : 5 in MeCN (1, 3, 4) or DMF (2), whereas compound 5 was prepared from the reaction of FeCl3 with Hap in the presence of HO2CC(CH3)(3) in a molar ratio 1 : 3 : 2 in MeCN. To the best of our knowledge, 1-5 are the first examples of Fe3+ complexes with the ligands Hap and Hhmpip. The structures of 1-4 are composed of a quasi-planar [Fe-5(mu(3)-O)(2)](11+) core which consists of two vertex-sharing [Fe-3(mu(3)-O)](7+) triangles. The structure of 5 is based on the [Fe-5(mu(4)-O)(mu(3)-O)](11+) core, in which the five Fe3+ ions adopt a monocapped trigonal pyramidal topology. Variable-temperature magnetic susceptibility measurements on powdered microcrystalline samples of 1 and 5 revealed the existence of antiferromagnetic interactions which led to an S = 5/2 ground state. Mossbauer spectroscopy studies on powdered microcrystalline samples of 1 and 5 confirmed that all iron ions of both complexes are in the Fe3+ (S = 5/2) state. The variation of the ligand environment in the various iron sites was reflected in their different quadruple splitting parameters. At T < 50 K the Mossbauer spectra indicated the onset of spin relaxation effects in the time scale of the technique (10(-7)-10(-8) s).
Περιγραφή
Λέξεις-κλειδιά
single-molecule magnet, transition-metal clusters, high-spin molecules, ground-state, coordination polymers, family, iron, alkoxides, tetranuclear, relaxation
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000299054500019
http://pubs.rsc.org/en/Content/ArticleLanding/2012/DT/c1dt11487e
http://pubs.rsc.org/en/Content/ArticleLanding/2012/DT/c1dt11487e
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας