The simultaneous crystallization of different polymorphs, i.e. concomitant polymorphism, is a phenomenon which, when properly recognized and studied, can provide useful information for a variety of disciplines. It is rare for ruthenium complexes, although it has been observed. In the synthesis of the ruthenium(II) complex chlorido(η6-p-cymene)(dimethyl 2,2′-bypyridine-4,5-dicarboxylate-κ2
N,N′)ruthenium(II) hexafluoridophosphate, [RuCl(C10H14)(C14H12N2O4)]PF6, concomitant polymorphs were crystallized under the same conditions. The colour of both crystals was orange, but the shapes, as well as the orientation of the p-cymene and methoxycarbonyl groups, were different. The crystal structures of both isomers show approximately the same bond lengths. In the asymmetric unit, there is one cation and one anion. Due to the absence of strong hydrogen bonds, only weak intermolecular interactions were observed. The Hirshfeld surface and two-dimensional fingerprint plots of both isomers satisfactorily explain the difference in the melting points.
不同多晶型的同时结晶(即伴随多晶型)是一种现象,如果认识和研究得当,可以为各种学科提供有用的信息。这种现象在
钌络合物中比较罕见,但也曾被观察到。在合成
钌(II)络合物 chlorido(η6-p-cymene)(dimethyl 2,2′-bypyridine-4,5-dicarboxylate-κ2
在相同条件下,结晶出了[RuCl(
C10H14)(
C14H12N2O4)]PF6(N,N′)
六氟磷酸钌(II)。两种晶体的颜色均为橙色,但形状以及
对伞花烃基和甲氧基羰基的取向均不同。两种异构体的晶体结构显示出大致相同的键长。在不对称单元中,有一个阳离子和一个阴离子。由于缺乏强氢键,只能观察到微弱的分子间相互作用。两种异构体的 Hirshfeld 表面和二维指纹图都能很好地解释熔点的差异。