Cover Feature: A Double‐Band Emitter with Ultranarrow‐Band Blue and Narrow‐Band Green Luminescence (Chem. Eur. J. 10/2020)

Eu2+‐doped UCr4C4‐type alkali lithosilicates exhibit green towards cyan and blue luminescence, depending on the exact composition. One possibility is that there are only sodium ions in the light‐alkali‐metal channel, leading the way left towards blue luminescence. However, pure lithium channels result in a green luminescence, pointing to the right turnoff. If mixed channels exist, it is the middle ground: presumably domain formation occurs, leading to a cyan double‐band emission. More information can be found in the Full Paper by H. Huppertz et al. on page 2204.