Bis(nitroxyl) Adducts of Cobalt and Nickel Hexafluoroacetylacetonates. Preparation, Structures, and Magnetic Properties of M(F6acac)2(proxyl)2 (M: Co2+, Ni2+).
Bis(nitroxyl) Adducts of Cobalt and Nickel Hexafluoroacetylacetonates. Preparation, Structures, and Magnetic Properties of M(F6acac)2(proxyl)2 (M: Co2+, Ni2+).
复制标题
六氟乙酰丙酮钴和镍的双（硝酰基）加合物。
DOI：
10.1002/chin.198834269
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
R. Doedens
中科院分区：
文献类型：
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作者：
L. Porter;M. Dickman;R. Doedens
制备了环状硝酰基2,2,5,5-四甲基吡咯烷基-1-氧基（丙氧基）与六氟乙酰丙酮镍（II）和钴（II）的双加合物，并通过晶体结构分析和磁化率研究对其进行了表征。加合物是同构的，各自具有中心对称的分子结构和关于金属离子的稍微扭曲的八面体构型。 O-结合的硝酰基采用反式构型。磁化率数据 (6-300 K) 表明配体和金属自由自旋的反铁磁耦合对于 M= Co2+ 产生 S='/2 基态，对于 M= Ni2+ 产生 S= 0 基态。在较高温度下，存在一些具有更大自旋多重性的激发态群。讨论了可以解释磁性行为的可能轨道相互作用。 Co (F6acac) 2 (proxyl) 2 的晶体数据：单斜晶系，空间群 P2x¡ c，Z= 2，a= 10.339 (4) Á，b= 14.533 (4) A，c= 11.973 (4) Á，ß= 111.09 (2)。基于 1615 个数据的最小二乘细化，Fa2 34> 3n (F02) 且 2< 50 收敛至 R= 0.056。 Ni (F6acac) 2 (proxyl) 2 的晶体数据：单斜晶系，空间群 P2¡/c，Z- 2，a= 10.243 (5) k，b= 14.564 (5) Á，c= 11.902 (5) Á。基于 1609 个非零数据的最小二乘细化，其中 2< 45 收敛至 R= 0.052。
Bisadducts of the cyclic nitroxyl radical 2, 2, 5, 5-tetramethylpyrrolidinyl-l-oxy (proxyl) with nickel (II) and cobalt (II) hexa-fluoroacetylacetonates havebeen prepared and characterized by crystal structure analyses and magnetic susceptibility studies. The adducts are isostructural, each having a centrosymmetric molecular structure and a slightly distorted octahedral configuration about the metal ion. The O-bound nitroxyls adopt a trans configuration. Magnetic susceptibility data (6-300 K) indicate that antiferromagnetic coupling of ligand and metal freespins yields an S='/2 ground state for M= Co2+ and an S= 0 ground state for M= Ni2+. At higher temperatures, there is some population of excitedstates with greater spin multiplicities. Possible orbital interactions that could account for the magnetic behavior are discussed. Crystal data for Co (F6acac) 2 (proxyl) 2: monoclinic, space group P2x¡ c, Z= 2, a= 10.339 (4) Á, b= 14.533 (4) A, c= 11.973 (4) Á, ß= 111.09 (2). Least-squares refinement based upon 1615 datawith Fa2 34> 3n (F02) and 2< 50 converged to R= 0.056. Crystal data for Ni (F6acac) 2 (proxyl) 2: monoclinic, space group P2¡/c, Z- 2, a= 10.243 (5) k, b= 14.564 (5) Á, c= 11.902 (5) Á. Least-squares refinement based upon 1609 nonzero data with 2< 45 convergedto R= 0.052.