malonate occur. Compound 2 has a three-dimensional structure with a structural phase transition at 226 K, which involves a change of the space group from I2/a to Ia. Although its structure at room temperature was already known, that below 226 K was not. Pairs of Gd atoms with a double oxo-carboxylate bridge occur in both phases, and the main differences between both structures deal with the Gd environment
四种g与具有式[Gd2(mal)3(
H2O)5] n.2n (1),[Gd2(mal)3( )6] n(2),[NaGd(mal)的二
羧酸酯
配体的配合物制备了(ox)( )3] n(3)和[Gd2(ox)3( )6] n.2.5n (4)(mal =
丙二酸酯; ox =
草酸酯),其磁性能为被研究作为温度的函数。1-3的结构已经通过X射线衍射法确定。4的晶体结构是已知的,它由Gd原子的六角形层组成,该层由双双齿
草酸盐桥接。化合物1与
丙二酸((III)配合物[Eu2(mal)3( )5] n.2n ,1是同构的,其结构已在别处报道。1中的Gd原子定义了一个二维网络,在该网络中发生了
丙二酸的末端双齿和桥联双齿/双单齿和三双齿配位模式。化合物2具有三维结构,在226 K处具有结构相变,这涉及空间基团从I2 / a到Ia的变化。尽管其在室温下的结构是已知的,但低于226