Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Québec, Canada H3A 0B8.
Ruđer Bošković Institute, Bijenička cesta 54, Zagreb, HR-10000, Croatia.
Nat Commun. 2015 Mar 23;6:6662. doi: 10.1038/ncomms7662.
Chemical and physical transformations by milling are attracting enormous interest for their ability to access new materials and clean reactivity, and are central to a number of core industries, from mineral processing to pharmaceutical manufacturing. While continuous mechanical stress during milling is thought to create an environment supporting nonconventional reactivity and exotic intermediates, such speculations have remained without proof. Here we use in situ, real-time powder X-ray diffraction monitoring to discover and capture a metastable, novel-topology intermediate of a mechanochemical transformation. Monitoring the mechanochemical synthesis of an archetypal metal-organic framework ZIF-8 by in situ powder X-ray diffraction reveals unexpected amorphization, and on further milling recrystallization into a non-porous material via a metastable intermediate based on a previously unreported topology, herein named katsenite (kat). The discovery of this phase and topology provides direct evidence that milling transformations can involve short-lived, structurally unusual phases not yet accessed by conventional chemistry.
机械球磨过程中的化学和物理转化因其能够获得新材料和清洁反应性而引起了极大的关注，并且是许多核心产业（从矿物加工到制药制造）的核心。虽然人们认为在球磨过程中连续的机械应力会创造一个支持非常规反应性和奇特中间体的环境，但这些推测仍然没有得到证实。在这里，我们使用原位、实时粉末 X 射线衍射监测来发现和捕获机械化学转化的亚稳、新颖拓扑中间体。通过原位粉末 X 射线衍射监测典型的金属有机骨架 ZIF-8 的机械化学合成，揭示了意想不到的非晶化，并且在进一步球磨过程中通过基于以前未报道的拓扑结构的亚稳中间体再结晶成无孔材料，本文命名为 katsenite（kat）。该相和拓扑结构的发现提供了直接证据，证明球磨转化可能涉及短寿命的、结构上不寻常的相，这些相尚未通过传统化学方法获得。
