Assembling hexagonal-bipyramidal {Mn8Zn2} and {Mn8Zn4} clusters

Tziotzi, T. G., Andreou, E. K., Mavromagoulos, A., Murrie, M. , Dalgarno, S. J., Brechin, E. K. and Milios, C. J. (2022) Assembling hexagonal-bipyramidal {Mn8Zn2} and {Mn8Zn4} clusters. European Journal of Inorganic Chemistry, 2022(32), e202200434. (doi: 10.1002/ejic.202200434)

Abstract

Reaction between Mn(NO3)2 ⋅ 6H2O, Zn(NO3)2 ⋅ 6H2O, 1,3,5-tri(2-hydroxyethyl)-1,3,5-triazacyclohexane (H3L) and pyrazole in MeOH under basic conditions leads to the formation of the decanuclear complex [MnIII6MnII2ZnII2(L)2(pyr)4O4(OH)4(NO3)2 (MeOH)2(H2O)4](NO3)2 ⋅ Η2Ο (1 ⋅ Η2Ο). The metallic core of the cationic cluster consists of a central hexagonal-bipyramidal {MnIII4MnII2ZnII2} unit connected to two peripheral trivalent Mn centers arranged in a “trans” fashion, with one MnIII center lying above and one MnIII center below the hexagonal plane. Replacing Mn(NO3)2 ⋅ 6H2O with MnBr2 ⋅ 4H2O and repeating the same reaction leads to the formation of the related, neutral decanuclear complex [MnIII6MnII2ZnII2(L)2(pyr)4O4(OH)4Br4(H2O)2] (2), displaying the same metallic core as 1. Addition of THF to the reaction mixture that produces (2) affords the neutral dodecanuclear complex [MnIII6MnII2ZnII4(L)2(pyr)6O4(OH)4Br6(H2O)4] ⋅ 8THF (3 ⋅ 8THF), whose metallic skeleton retains the central hexagonal-bipyramidal {MnIII4MnII2ZnII2} unit found in 1 and 2 but is now connected to two peripheral {MnIIIZnII} units. Magnetic susceptibility and magnetization measurements carried out in the T=2–300 K temperature range and in fields up to B=7.0 T for all three complexes reveal dominant antiferromagnetic exchange interactions.

• Item Type: Articles
• Additional Information: C.J.M. and T.G.T. thank the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the procurement of high-cost research equipment grant” (Project Number: 400). E.K.B. thanks the EPSRC for financial support under grant reference number EP/V010573/1. M.M. thanks the University of Glasgow for financial support.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Mavromagoulos, Athanasios and Murrie, Professor Mark
• Authors: Tziotzi, T. G., Andreou, E. K., Mavromagoulos, A., Murrie, M., Dalgarno, S. J., Brechin, E. K., and Milios, C. J.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: European Journal of Inorganic Chemistry
• Publisher: Wiley
• ISSN: 1434-1948
• ISSN (Online): 1099-0682
• Published Online: 16 August 2022
• Copyright Holders: Copyright © 2022 John Wiley & Sons
• First Published: First published in European Journal of Inorganic Chemistry 2022(32): 202200434
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher