Synthesis, Structure, and Magnetic Properties of 1D {[MnIII(CN)6][MnII(dapsc)]}n Coordination Polymers: Origin of Unconventional Single-Chain Magnet Behavior

Valentina D Sasnovskaya; Vyacheslav A Kopotkov; Artem D Talantsev; Roman B Morgunov; Eduard B Yagubskii; Sergey V Simonov; Leokadiya V Zorina; Vladimir S Mironov

doi:10.1021/acs.inorgchem.7b00676

Synthesis, Structure, and Magnetic Properties of 1D {[Mn^III(CN)₆][Mn^II(dapsc)]}_n Coordination Polymers: Origin of Unconventional Single-Chain Magnet Behavior

Inorg Chem. 2017 Aug 7;56(15):8926-8943. doi: 10.1021/acs.inorgchem.7b00676. Epub 2017 Jul 7.

Authors

Valentina D Sasnovskaya¹, Vyacheslav A Kopotkov¹, Artem D Talantsev¹, Roman B Morgunov¹, Eduard B Yagubskii¹, Sergey V Simonov², Leokadiya V Zorina², Vladimir S Mironov³

Affiliations

¹ Institute of Problems of Chemical Physics, Russian Academy of Sciences , Semenov's av., 1, Chernogolovka, MD, Russian Federation.
² Institute of Solid State Physics, Russian Academy of Sciences , Academician Ossipyan str., 2, Chernogolovka, MD, Russian Federation.
³ Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics", Russian Academy of Sciences , Leninskii av. 59, Moscow, Russian Federation.

PMID: 28686422
DOI: 10.1021/acs.inorgchem.7b00676

Abstract

Two one-dimensional cyano-bridged coordination polymers, namely, {[Mn^II(dapsc)][Mn^III(CN)₆][K(H₂O)_2.75(MeOH)_0.5]}_n·0.5n(H₂O) (I) and {[Mn^II(dapsc)][Mn^III(CN)₆][K(H₂O)₂(MeOH)₂]}_n (II), based on alternating high-spin Mn^II(dapsc) (dapsc = 2,6-diacetylpyridine bis(semicarbazone)) complexes and low-spin orbitally degenerate hexacyanomanganate(III) complexes were synthesized and characterized structurally and magnetically. Static and dynamic magnetic measurements reveal a single-chain magnet (SCM) behavior of I with an energy barrier of U_eff ≈ 40 K. Magnetic properties of I are analyzed in detail in terms of a microscopic theory. It is shown that compound I refers to a peculiar case of SCM that does not fall into the usual Ising and Heisenberg limits due to unconventional character of the Mn^III-CN-Mn^II spin coupling resulting from a nonmagnetic singlet ground state of orbitally degenerate complexes [Mn^III(CN)₆]^3-. The prospects of [Mn^III(CN)₆]^3- complex as magnetically anisotropic molecular building block for engineering molecular magnets are critically analyzed.