Speaker
Mr
Michał Magott
(Faculty of Chemistry, Jagiellonian University, Kraków)
Description
We have synthesized two new coordination chain compounds consisting of manganese(II), 2,2'-bipyridyl and octacyanoniobate(IV), both of them exhibiting ferromagnetic ordering. The first one [MnII(bpy)(H2O)2]2[Nb(CN)8]•5H2O 1 is isostructural with the manganese-octacyanotungstate vertex-sharing squares chain already reported by Ohkoshi et al. [1], while the second one [MnII(bpy)(H2O)2][Mn(bpy)2][Nb(CN)8]•4H2O 2 shows a topology that has not been observed yet and can be described as a chain of perpendicularly laying squares. Both compounds exhibit antiferromagnetic intrachain interactions within the NbIV-CN-MnII structural motifs typical for manganese-octacyanoniobate compounds, but also long-range ferromagnetic ordering (LRFO) below their critical temperatures (Tc) of 7.0 and 5.3 K, respectively, which is quite unusual for one-dimensional topology [2,3,4]. This can be explained only on the basis of significant ferromagnetic interchain interactions, which are assured by the interchain π-π contacts of the bipyridine rings and hydrogen bonds between coordination and crystallization water molecules. Additionally, although both chains show great structural similarity, a distinct difference in the octacyanoniobate(IV) geometry is observed, which might have some impact on the magnetic properties.
[1] Noriaki Ozaki, Ryo Yamada, Koji Nakabayashi, Shin-ichi Ohkoshi, Acta Crystallographica Section E, 2011, E67, m702-703
[2] Olivier Kahn, Molecular Magnetism, VCH, Weinheim 1993
[3] Rabindranath Pradhan, Cedric Desplanches, Philippe Guionneau, Jean-Pascal Sutter, Inorganic Chemistry, 2003, 42, 6607-6609
[4] Xiangyu Liu et al., Dalton Transactions, 2014, 43, 15359
Primary authors
Dr
Dawid Pinkowicz
(Faculty of Chemistry, Jagiellonian University, Kraków)
Mr
Michał Magott
(Faculty of Chemistry, Jagiellonian University, Kraków)
Co-author
Prof.
Barbara Sieklucka
(Faculty of Chemistry, Jagiellonian University, Kraków)
