Gas Electron Diffraction and Small Molecule Structures Centre, Bielefeld (GED@BI)

准确的分子结构是了解化学反应活性和分子性质的关键。我们建议建立一个国际核心设备(GED@BI)，利用两种专门技术：气体电子衍射(GED)和原位生长晶体的X射线衍射(XRD)来确定小分子的结构。GED是研究自由分子最有效的方法，不受分子间相互作用的影响。它是对单晶X射线衍射法的补充。X射线衍射法是晶体样品的标准方法，如果它们在衍射仪上直接(原位)结晶，则可以扩展到液体或气体。此外，X射线衍射仪还可以测定电子密度分布。所提出的方法在许多情况下是唯一适用于确定新化合物结构的方法。它们在基础和应用化学科学中得到应用，特别是研究分子间或分子内的弱相互作用、不寻常的成键情况、构象行为、簇合物等。比较气体和固体的结构提供了关于分子间相互作用的结构后果的信息。GED数据还可以用来验证或反驳量子化学单分子计算。核心设施GED@BI运行着全球最先进的高分辨率GED仪器，也是欧盟唯一的高分辨率GED仪器。它是为数不多的原位生长晶体的X射线衍射场之一。它拥有广泛的国际用户群体，保证两种重要方法的可持续运行，确保进一步的方法开发和青年科学家的教育，并将展示成功的管理和融资理念。

Accurate molecular structures are the key for understanding chemical reactivity and molecular properties. We propose to establish an international core facility (GED@BI) for structure determination of small molecules by two specialized techniques: gas electron diffraction (GED) and X-ray diffraction (XRD) of in-situ grown crystals. GED is the most powerful method for investigating free molecules, undistorted by intermolecular interactions. It is complementary to single-crystal XRD. XRD is the standard method for crystalline samples and can be extended to liquids or gases, if they are crystallized directly (in situ) on a diffractometer. In addition, XRD allows determining electron density distributions. The proposed methods are in many cases the only applicable to determine the structure of new compounds. They find applications in fundamental and applied chemical science, in particular to study weak inter- or intramolecular interactions, unusual bonding situations, conformational behaviour, cluster compounds and many more. Comparing gas and solid state structures provides information on structural consequences of intermolecular interactions. GED data also serve to validate or disprove quantum-chemical single-molecule calculations. The core facility GED@BI runs the most modern instrument for high-resolution GED worldwide and the only one in the EU. It is one of few places for XRD of in-situ grown crystals. It has a wide group of international users, guarantees sustainable operation of two important methods, secures further method development, education of young scientists, and will demonstrate successful management and financing concepts.