New iron tetrazolate frameworks : synthesis temperature effect, thermal behaviour, Mössbauer and magnetic studies
Abstract
The exploration of the FeF3/FeF2-Hamtetraz-HF system in dimethylformamide by solvothermal synthesis evidences two isostructural 3D hybrid fluoroferrates. They are prepared from the same starting mixture at two different synthesis temperatures: 120 °C for [Hdma]·(Fe4IIFeIIIF8(H2O)2(amtetraz)4) (1) and 140 °C for [Hdma]1.5·(Fe4.5IIFe0.5IIIF7(H2O)(HCOO)(amtetraz)4) (2). Both compounds are characterized by single crystal X-ray diffraction, X-ray thermodiffraction, TGA analysis, Mössbauer spectrometry and SQUID magnetometry. They crystallize in the monoclinic system and are built from two distinct chains connected by aminotetrazolate anions. The first chain ∞(FeIIFN4) is common to 1 and 2 and can be found in numerous fluorides. In the second chain ∞(Fe3X12) (X = F, N, O), iron cations adopt both valence states Fe(II)/Fe(III). The hydrolysis of DMF implies the formation of a [Hdma]+ cation and a (HCOO)− anion. The presence of Fe3+ in both phases is evidenced by 57Fe Mössbauer spectrometry. The magnetic properties are studied and two transitions from a paramagnetic regime to a long range ordered state below 30 K and 5 K are identified.
Citation
Pimenta , V , Le , Q H H , Clark , L M , Lhoste , J , Hémon-Ribaud , A , Leblanc , M , Grenèche , J-M , Dujardin , G , Lightfoot , P & Maisonneuve , V 2015 , ' New iron tetrazolate frameworks : synthesis temperature effect, thermal behaviour, Mössbauer and magnetic studies ' , Dalton Transactions , vol. 44 , no. 17 , pp. 7951-7959 . https://doi.org/10.1039/C5DT00281H
Publication
Dalton Transactions
Status
Peer reviewed
ISSN
1477-9226Type
Journal article
Rights
Copyright the Authors 2015. This work is made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at http://pubs.rsc.org/en/content/articlelanding/2015/dt/c5dt00281h#!divAbstract
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