TY - JOUR
T1 - Mixed-valence tetra- and hexanuclear manganese complexes from the flexibility of pyridine-containing β-diketone ligands
AU - Yang, Chen I.
AU - Wernsdorfer, Wolfgang
AU - Tsai, Yu Jhe
AU - Chung, George
AU - Kuo, Ting Shen
AU - Lee, Gene Hsiang
AU - Shieh, Minghuey
AU - Tsai, Hui Lien
PY - 2008/3/17
Y1 - 2008/3/17
N2 - The reactions of [Mn3O(O2CCCl3) 6(H2O)3] with 1-phenyl-3-(2-pyridyl)propane-1, 3-dione (HL1) and 1-(2-pyridly)-3-(p-tolyl)propane-1,3-dione (HL 2) in CH2Cl2 afford the mixed-valence Mn II2MnIII2 tetranuclear complexes [Mn4O-(O2CCCl3)6(L1) 2] (1) and [Mn4O(O2CCCl3) 6L22] (2), respectively. Similar reactions employing [Mn3O(O2CPh)6(H2O)(py) 2] with HL1 and HL2 give the Mn II3MnIII3 hexanuclear complexes [Mn6O2(O2CPh)8(L1) 3] (3) and [Mn6O2(O2CPh) 8L32] (4), respectively. Complexes 1·2CH2Cl2, 2·2CH2Cl 2·H2O, 3·1.5CH2Cl 2·Et2O·H2O, and 4·2CH 2Cl2 crystallize in the triclinic space group P1, monoclinic space group P21/c, monoclinic space group P2 1/n, and monoclinic space group P21/n, respectively. Complexes 1 and 2 consist of a trapped-valence tetranuclear core of [Mn II2MnIII2(μ4-0)] 8+, and complexes 3 and 4 represent a new structural type, possessing a [MnII3MnIII3(μ4-O) 2]11+ core. The magnetic data indicate that complexes 3 and 4 have a ground-state spin value of S = 7/2 with significant magnetoanisotropy as gauged by the D values of -0.51 cm-1 and -0.46 cm-1, respectively, and frequency-dependent out-of-phase signals in alternating current magnetic susceptibility studies indicate their superparamagnetic behavior. In contrast, complexes 1 and 2 are low-spin molecules with an S = 1 ground state. Single-molecule magnetism behavior confirmed for 3 the presence of sweep-rate and temperature-dependent hysteresis loops in single-crystal M versus H studies at temperatures down to 40 mK.
AB - The reactions of [Mn3O(O2CCCl3) 6(H2O)3] with 1-phenyl-3-(2-pyridyl)propane-1, 3-dione (HL1) and 1-(2-pyridly)-3-(p-tolyl)propane-1,3-dione (HL 2) in CH2Cl2 afford the mixed-valence Mn II2MnIII2 tetranuclear complexes [Mn4O-(O2CCCl3)6(L1) 2] (1) and [Mn4O(O2CCCl3) 6L22] (2), respectively. Similar reactions employing [Mn3O(O2CPh)6(H2O)(py) 2] with HL1 and HL2 give the Mn II3MnIII3 hexanuclear complexes [Mn6O2(O2CPh)8(L1) 3] (3) and [Mn6O2(O2CPh) 8L32] (4), respectively. Complexes 1·2CH2Cl2, 2·2CH2Cl 2·H2O, 3·1.5CH2Cl 2·Et2O·H2O, and 4·2CH 2Cl2 crystallize in the triclinic space group P1, monoclinic space group P21/c, monoclinic space group P2 1/n, and monoclinic space group P21/n, respectively. Complexes 1 and 2 consist of a trapped-valence tetranuclear core of [Mn II2MnIII2(μ4-0)] 8+, and complexes 3 and 4 represent a new structural type, possessing a [MnII3MnIII3(μ4-O) 2]11+ core. The magnetic data indicate that complexes 3 and 4 have a ground-state spin value of S = 7/2 with significant magnetoanisotropy as gauged by the D values of -0.51 cm-1 and -0.46 cm-1, respectively, and frequency-dependent out-of-phase signals in alternating current magnetic susceptibility studies indicate their superparamagnetic behavior. In contrast, complexes 1 and 2 are low-spin molecules with an S = 1 ground state. Single-molecule magnetism behavior confirmed for 3 the presence of sweep-rate and temperature-dependent hysteresis loops in single-crystal M versus H studies at temperatures down to 40 mK.
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U2 - 10.1021/ic7013368
DO - 10.1021/ic7013368
M3 - Article
C2 - 18290611
AN - SCOPUS:42149152192
SN - 0020-1669
VL - 47
SP - 1925
EP - 1939
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 6
ER -