Yongming Han

© 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.Metal-organic frameworks are crystalline porous materials with designable topology, porosity and functionality, having promising applications in gas storage and separation, ion conduction and catalysis. It is challenging to observe MOFs with transmission electron microscopy due to the extreme instability of MOFs upon electron beam irradiation. Here, we use a direct-detection electron-counting camera to acquire TEM images of the MOF ZIF-8 with an ultralow dose of 4.1 electrons per square ångström to retain the structural integrity. The obtained image involves structural information transferred up to 2.1 Å, allowing the resolution of individual atomic columns of Zn and organic linkers in the framework. Furthermore, TEM reveals important local structural features of ZIF-8 crystals that cannot be identified by diffraction techniques, including armchair-type surface terminations and coherent interfaces between assembled crystals. These observations allow us to understand how ZIF-8 crystals self-assemble and the subsequent influence of interfacial cavities on mass transport of guest molecules.

Do we love for reasons? It can seem as if we do, since most cases of non‐familial love seem *selective*: coming to love a non‐family‐member often begins with our being drawn to them for what they are like. I argue, however, that we can vindicate love's selectivity, even if we maintain that there are no reasons for love; indeed, that gives us a simpler, and hence better, explanation of love's selectivity. We don't, in short, come to love *for* reasons. That which seemed like evidence for thinking that there are reasons for love, then, turns out to militate against that view: how can these purported reasons be reasons for love, if they don't engender (in virtue of rationalizing) it?