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Abstract：
The oxidation of tetraselenatetracene (TSeT) by tetracyanoquinodimethane in the presence of dysprosium(III) tris(hexafluoroacetylacetonate), DyIII(hfac)3, produces black crystals of {TSeT1.5}●+[DyIII(hfac)4]- (1) salt, which combines conducting and magnetic sublattices. It contains one-dimensional stacks composed of partially oxidized TSeT molecules (formal averaged charge is +2/3). Dimers and monomers can be outlined within these stacks with charge and spin density redistribution. The spin triplet state of the dimers is populated above 128 K with an estimated singlet-triplet energy gap of 542 K, whereas spins localized on the monomers show paramagnetic behavior. A semiconducting behavior is observed for 1 with the activation energy of 91 meV (measured by the four-probe technique for an oriented single crystal). The DyIII ions coordinate four hfac- anions in [DyIII(hfac)4]-, providing D2d symmetry. Slow magnetic relaxation is observed for DyIII under an applied static magnetic field of 1000 Oe, and 1 is a single-ion magnet (SIM) with spin reversal barrier Ueff = 40.2 K and magnetic hysteresis at 2 K. Contributions from DyIII and TSeT●+ paramagnetic species are seen in EPR. The DyIII ion rarely manifests EPR signals, but such signal is observed in 1. It appears due to narrowing below 30 K and has g4 = 6.1871 and g5 = 2.1778 at 5.4 K.
摘要：
在三（六氟乙酰丙酮）的存在下，四苯并喹二甲烷对四苯并（TSeT）的氧化，DyIII(hfac)3,产生{TSeT1.5}●+[DyIII(hfac)4]-(1)盐的黑色晶体,结合了导电和磁性亚晶格。它包含由部分氧化的TSeT分子组成的一维堆叠（形式平均电荷为2/3）。二聚体和单体可以在这些具有电荷和自旋密度重新分布的堆叠内勾勒出来。二聚体的自旋三重态填充在128K以上，估计的单重态三重态能隙为542K，而位于单体上的自旋显示顺磁性。观察到1的半导体行为，活化能为91meV（通过四探针技术对取向单晶进行测量）。DyIII离子配位[DyIII（hfac）4]-中的四个hact-阴离子，提供D2d对称性。在施加1000Oe的静磁场下，DyIII观察到缓慢的磁弛豫，1是单离子磁体（SIM），自旋反转势垒Ueff=40.2K，磁滞在2K。在EPR中可以看到DyIII和TSeT●顺磁性物种的贡献。DyIII离子很少显示EPR信号,但在1中观察到这样的信号。由于缩小到30K以下而出现，并且在5.4K时g4=6.1871和g5=2.1778。
