TY - JOUR
T1 - Cyanide-bridged Fe(III)-Mn(III) bimetallic systems assembled from the fac -Fe tricyanide and Mn schiff bases
T2 - Structures, magnetic properties, and density functional theory calculations
AU - Kwak, Hyun Young
AU - Ryu, Dae Won
AU - Lee, Jin Wuk
AU - Yoon, Jung Hee
AU - Kim, Hyoung Chan
AU - Koh, Eui Kwan
AU - Krinsky, Jamin
AU - Hong, Chang Seop
PY - 2010/5/17
Y1 - 2010/5/17
N2 - Reaction of [(Tp)Fe(CN)3]- [Tp = hydrotris(pyrazolyl) borate] with respective Mn(III) Schiff bases led to the formation of four dimeric molecules, [(Tp)Fe(CN)3][Mn(1-napen)(H2O)] ·MeCN·4H2O [1; 1-napen = N,N′-ethylenebis(2- hydroxy-1-naphthylideneiminato) dianion], [(Tp)Fe(CN)3][Mn(5-Clsalen) (H2O)] [2; 5-Clsalcy = N,N′-(trans-1,2-cyclohexanediylethylene) bis(5-chlorosalicylideneiminato) dianion], [(Tp)Fe(CN)3][Mn(2- acnapen)(MeOH)]·MeOH [3; 2-acnapen = N,N′-ethylenebis(1-hydroxy-2- acetonaphthylideneiminato) dianion], [(Tp)Fe(CN)3][Mn(3-MeOsalen) (H2O)] [4; 3-MeOsalen = N,N′-ethylenebis(3- methoxysalicylideneiminato) dianion], and a one-dimensional (1D) zigzag chain [(Tp)Fe(CN)3][Mn(2-acnapen)]·H2O (5). The dimers contain multiple intermolecular interactions such as hydrogen bonds, face-to-face π-π contacts, and edge-to-face CH-π forces, raising molecular dimensions from one-dimensional (1D) up to three-dimensional (3D) arrays, whereas there are no π-π stacking interactions in the 1D chain compound. Magnetic measurements reveal that ferromagnetic couplings are obviously operative between Mn(III) and Fe(III) spin centers transmitted by CN bridges for 1-3 and 5, and antiferromagnetic interactions are however unexpectedly present in 4. On the basis of the proper spin Hamiltonians, magnetic exchange couplings are estimated to be in the span from 1.79 to 7.48 cm-1 for the ferromagnetically coupled systems and -1.40 cm -1 for the antiferromagnetic dimer. A slow magnetic relaxation is tangible in 5, which is in connection with isolated chains devoid of any intermolecular noncovalent interactions. Density Functional Theory (DFT) calculations and comparison of structural parameters suggest that the observed magnetic behaviors are mainly associated with the bending of the Mn-N-C angle in the bridging pathway.
AB - Reaction of [(Tp)Fe(CN)3]- [Tp = hydrotris(pyrazolyl) borate] with respective Mn(III) Schiff bases led to the formation of four dimeric molecules, [(Tp)Fe(CN)3][Mn(1-napen)(H2O)] ·MeCN·4H2O [1; 1-napen = N,N′-ethylenebis(2- hydroxy-1-naphthylideneiminato) dianion], [(Tp)Fe(CN)3][Mn(5-Clsalen) (H2O)] [2; 5-Clsalcy = N,N′-(trans-1,2-cyclohexanediylethylene) bis(5-chlorosalicylideneiminato) dianion], [(Tp)Fe(CN)3][Mn(2- acnapen)(MeOH)]·MeOH [3; 2-acnapen = N,N′-ethylenebis(1-hydroxy-2- acetonaphthylideneiminato) dianion], [(Tp)Fe(CN)3][Mn(3-MeOsalen) (H2O)] [4; 3-MeOsalen = N,N′-ethylenebis(3- methoxysalicylideneiminato) dianion], and a one-dimensional (1D) zigzag chain [(Tp)Fe(CN)3][Mn(2-acnapen)]·H2O (5). The dimers contain multiple intermolecular interactions such as hydrogen bonds, face-to-face π-π contacts, and edge-to-face CH-π forces, raising molecular dimensions from one-dimensional (1D) up to three-dimensional (3D) arrays, whereas there are no π-π stacking interactions in the 1D chain compound. Magnetic measurements reveal that ferromagnetic couplings are obviously operative between Mn(III) and Fe(III) spin centers transmitted by CN bridges for 1-3 and 5, and antiferromagnetic interactions are however unexpectedly present in 4. On the basis of the proper spin Hamiltonians, magnetic exchange couplings are estimated to be in the span from 1.79 to 7.48 cm-1 for the ferromagnetically coupled systems and -1.40 cm -1 for the antiferromagnetic dimer. A slow magnetic relaxation is tangible in 5, which is in connection with isolated chains devoid of any intermolecular noncovalent interactions. Density Functional Theory (DFT) calculations and comparison of structural parameters suggest that the observed magnetic behaviors are mainly associated with the bending of the Mn-N-C angle in the bridging pathway.
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U2 - 10.1021/ic100301q
DO - 10.1021/ic100301q
M3 - Article
C2 - 20402476
AN - SCOPUS:77952139906
SN - 0020-1669
VL - 49
SP - 4632
EP - 4642
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 10
ER -