Inside Back Cover: Ultralong Room‐Temperature Phosphorescence from Boric Acid (Angew. Chem. Int. Ed. 17/2021)

The impressive and unexpected long-lived room-temperature phosphorescence of boric acid (H3BO3) is unveiled by Peng Wu and co-workers in their Research Article on page 9500. Unlike traditional metallic inorganic or aromatic organic phosphors, the phosphorescence originates from the weak conjugation of lone pair electrons from O atoms. The vacant pz orbital of B and the regular arrangement in the crystalline state with layer-like packing through abundant hydrogen bonding are found to contribute to the long-lived emission.