Conglomerate Crystallization in the CSD (2020–2021)

Abstract

Conglomerate crystals are materials capable of undergoing spontaneous resolution and were responsible for the discovery of molecular chirality. Their relevance to modern chemical and crystallographic sciences has been hindered by the difficulty in identifying and searching materials with this characteristic ability to bias their own enantioenrich- ment. With the release of the November 2021 distribution of the CSD (version 5.43), a fresh quantity of chiral conglomerate crystals is expected to have been published in the CSD without identification. Indeed, no crystals in the CSD have been identified as a spontaneously resolving conglomerate crystal in their CIF since the 2019 release, despite the deposition of over 108,000 new crystal structures into the database over the same time period. A manual inspection of crystals deposited between 2020–2021 was conducted to identify 343 new chiral materials which exhibit conglomerate crys- tallization behavior. It is hoped that the continued manual curation of this list will aid those in the crystallographic and synthetic communities to study and exploit this spontaneous enantioenrichment behavior.