Ferromagnetic Coupling between Copper(II) Centers through the Diamagnetic Zinc(II) Ion: Crystal Structure and Magnetic Properties of [Cu(2)Zn(Hdmg)(2)(dmg)(2)(H(2)O)].0.5H(2)dmg.H(2)O (H(2)dmg = Dimethylglyoxime).
Ferromagnetic Coupling between Copper(II) Centers through the Diamagnetic Zinc(II) Ion: Crystal Structure and Magnetic Properties of [Cu(2)Zn(Hdmg)(2)(dmg)(2)(H(2)O)].0.5H(2)dmg.H(2)O (H(2)dmg = Dimethylglyoxime).
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铜（II）中心之间通过反磁性锌（II）离子的铁磁耦合：[Cu(2)Zn(Hdmg)(2)(dmg)(2)(H(2)O)]的晶体结构和磁性。
作者：
R. Ruiz;M. Julve;J. Faus;F. Lloret;M. Muñoz;Y. Journaux;C. Bois
合成了一种新的异三核配合物[Cu(2)Zn(Hdmg)(2)(dmg)(2)(H(2)O)].0.5H(2)dmg.H(2)O (C(18)H(34)Cu(2)N(9)O(11)Zn, 1) (H(2)dmg =二甲基乙氧肟]，并用单晶x射线衍射测定了其晶体结构。结晶于三斜体系，空间群P&onemacr；，其中a = 11.414(1) Å， b = 11.992(3) Å， c =12.567（10） Å， alpha = 91.27(6)度，beta = 111.46(2)度，gamma = 112.24(2)度，Z = 2。该结构由中性的[Cu(2)Zn(Hdmg)(2)(dmg)(2)(H(2)O)]三核单元链和非配位的H(2)dmg和水分子组成。锌原子周围的构型是扭曲的三角双锥体，来自两个[Cu(Hdmg)(dmg)]（-）片段（每个片段通过其顺式去质子化的氧充当双齿配体）占据一个轴向位置和三个赤道位置，另外一个来自对称相关的[Cu(Hdmg)(dmg)]（-）片段的氧占据剩余的轴向位置。Cu(1)和Cu(2)周围的环境是扭曲的方锥体，四个氧态氮原子形成赤道面。来自水分子的氧原子[O(9)]和来自对称相关的[Cu(Hdmg)(dmg)]（-）片段的氧分别占据了Cu(1)和Cu(2)周围方形金字塔的顶端位置。三核单元通过位于Zn(1)中间的反转中心重复。Zn(1)(i)和Cu(2)。Cu(2)(2)(2)(2)个向量，指向与ac平面对角线平行的链。铜(1)。铜(2)、锌(1)。Zn(1)(i)和Cu(2)Cu(2)（ii）的分离度分别为5.506(2)、3.390(2)和3.930(2)Å。1表现出特有的铁磁行为，随着温度从300 K降低到2.0 K, chi(M)T积不断增加。2.0 K磁化强度的场依赖性与低洼五态一致。在1中，导致铁磁耦合的唯一有效交换途径是抗磁性锌（II）离子和面外双氧桥，铜（II）离子通过这些桥接单元之间的磁耦合强度分别为3.9和5.1 cm(-)(1)。
A new heterotrinuclear complex of formula [Cu(2)Zn(Hdmg)(2)(dmg)(2)(H(2)O)].0.5H(2)dmg.H(2)O (C(18)H(34)Cu(2)N(9)O(11)Zn, 1) (H(2)dmg = dimethylglyoxime) has been synthesized and its crystal structure determined by single-crystal X-ray diffraction. It crystallizes in the triclinic system, space group P&onemacr;, with a = 11.414(1) Å, b = 11.992(3) Å, c =12.567(10) Å, alpha = 91.27(6) degrees, beta = 111.46(2) degrees, gamma = 112.24(2) degrees, and Z = 2. The structure consists of a chain of neutral [Cu(2)Zn(Hdmg)(2)(dmg)(2)(H(2)O)] trinuclear units and noncoordinated H(2)dmg and water molecules. The configuration around the zinc atom is distorted trigonal bipyramidal with four oximate oxygens from two [Cu(Hdmg)(dmg)](-) fragments (each one acting as a bidentate ligand through its deprotonated oximate oxygens in cis positions) occupying one axial and the three equatorial positions and an additional oximate oxygen from a symmetry-related [Cu(Hdmg)(dmg)](-) fragment filling the remaining axial position. The environment around Cu(1) and Cu(2) is distorted square pyramidal with four oximate nitrogen atoms building the equatorial plane. An oxygen atom [O(9)] from a water molecule and an oximate oxygen from a symmetry-related [Cu(Hdmg)(dmg)](-) fragment occupy the apical position of the square pyramids around Cu(1) and Cu(2), respectively. The trinuclear units are repeated through inversion centers standing at the middle of the Zn(1).Zn(1)(i) and Cu(2).Cu(2)(ii) vectors leading to a chain which runs parallel to the diagonal of the ac-plane. The Cu(1).Cu(2), Zn(1).Zn(1)(i), and Cu(2).Cu(2)(ii) separations are 5.506(2), 3.390(2), and 3.930(2) Å, respectively. 1 exhibits a characteristic ferromagnetic behavior with a continuous increase of the chi(M)T product as the temperature is lowered from 300 to 2.0 K. The field dependence of the magnetization at 2.0 K is consistent with a low-lying quintet state. The only efficient exchange pathways responsible for the overall ferromagnetic coupling in 1 are the diamagnetic zinc(II) ion and the out-of-plane double-oximato bridge, the magnitude of the magnetic coupling between the copper(II) ions through these bridging units being 3.9 and 5.1 cm(-)(1), respectively.