Institut für anorganische Chemie, Universität Duisburg Essen, Universitätsstrasse 5, 45117 Essen, Germany.
Chemistry. 2010 Feb 15;16(7):2131-46. doi: 10.1002/chem.200901314.
Acetylene is an amazingly versatile component for the formation of co-crystals. It requires careful handling and special techniques for crystallisation, but the efforts seem to be rewarding when attaining co-crystals with small molecules as partners. Many basic questions such as the dominance of specific heterogeneous intermolecular interactions, their driving force for the formation of multicomponent crystals instead of neat ones are expected to be easily analysed. The underlying packing patterns and resulting stoichiometries based on the known supramolecular synthons seem to be straightforward for such small molecules and crystal engineering, considered as the prototype of supramolecular synthesis, should be a simple task. Nineteen co-crystals with acetylene are presented in this paper, some of which have been previously reported individually. An attempt has been made to find features shared by the groups of co-crystals, including those that could not be co-crystallised. But in spite of clear ideas and experiences from previous experiments, surprisingly almost none of systems reached our expectations. Our intuitive approach was not fulfilled, which demonstrates that multicomponent crystals even of small molecules will remain a great challenge for theoretical methods and the crystal structures shown herein represent good candidates for future testing. On the other hand, we wish to encourage other groups to present their views on the crystal structures with an unbiased approach that may offer a better explanation than we are able to outline in this article.
乙炔是形成共晶的一种非常通用的成分。它需要小心处理和特殊的结晶技术，但当与小分子作为伴侣获得共晶时，似乎所有的努力都是值得的。许多基本问题，如特定非均相分子间相互作用的主导地位、它们形成多组分晶体而不是纯净晶体的驱动力，预计可以很容易地进行分析。基于已知的超分子合成子，潜在的堆积模式和产生的化学计量似乎对于这些小分子来说是直接的，并且将晶体工程视为超分子合成的原型，应该是一项简单的任务。本文介绍了 19 个与乙炔的共晶，其中一些之前已单独报道过。我们试图找到共晶组之间的共同特征，包括那些不能共晶化的组。但是，尽管从之前的实验中得到了明确的想法和经验，令人惊讶的是，几乎没有一个系统达到了我们的预期。我们的直观方法没有得到满足，这表明即使是小分子的多组分晶体仍然是理论方法的一个巨大挑战，并且本文中所示的晶体结构代表了未来测试的良好候选者。另一方面，我们希望鼓励其他小组以公正的方式提出他们对晶体结构的看法，这可能比我们在本文中能够概述的更好地解释。
