Custelcean Radu, Gorbunova Maryna G, Bonnesen Peter V
Chemical Sciences Division, Oak Ridge National Laboratory, P.O. Box 2008, MS-6119, Oak Ridge, TN 37831-6119, USA.
Chemistry. 2005 Feb 18;11(5):1459-66. doi: 10.1002/chem.200400973.
Hydrogen bonding in crystalline N,N'-dialkylthioureas was examined with the help of single-crystal X-ray diffraction, DFT calculations, and Cambridge Structural Database (CSD) analysis. A CSD survey indicated that unlike the related urea derivatives, which persistently self-assemble into one-dimensional hydrogen-bonded chains, the analogous thioureas can form two different hydrogen-bonding motifs in the solid state: chains, structurally similar with those found in ureas, and dimers, that further associate into hydrogen-bonded layers. The formation of one motif or another can be manipulated by the bulkiness of the organic substituents on the thiourea group, which provides a clear example of steric control over the hydrogen bonding arrangement in crystalline organic solids.
借助单晶X射线衍射、密度泛函理论（DFT）计算以及剑桥结构数据库（CSD）分析，对晶体N,N'-二烷基硫脲中的氢键进行了研究。CSD调查表明，与相关的尿素衍生物持续自组装成一维氢键链不同，类似的硫脲在固态时可形成两种不同的氢键基序：与尿素中发现的结构相似的链，以及进一步缔合形成氢键层的二聚体。通过硫脲基团上有机取代基的体积大小，可以控制形成这一种或另一种基序，这为晶体有机固体中氢键排列的空间控制提供了一个清晰的例子。
