(551d) A Brief History of Exploring Hypothetical Crystal Structures

The ability to design a crystal, both in terms of its structure and function, is the defining quest of the field of 'crystal engineering.' Despite impressive progress over the past several decades, particularly among the class of crystals known as metal-organic frameworks (MOFs), it is by no means a solved problem. There are many distinct aspects to this challenge, one of which relates to the vastness of the sea of possible crystal structures that could plausibly be synthesized. Namely, if one wants to design "the best" crystal for a target application, how does one find it within that vast and deep sea? An even simpler question is troublingly difficult to address, just how vast is this sea exactly? Does the sea have a well-defined basin and coastline whose shape we are able to determine? Exploring the space of possible, or hypothetical, crystals is a task that many research groups have engaged in, each contributing their own insights toward these broad questions. In this talk I will (try to) briefly summarize the large body of past work on hypothetical crystal structure generation, along with my own drop in that ocean.