Abstract & Overview
The single-crystal synchrotron study of the high-pressure modification of aluminium oxide hydroxide, δ-AlOOH, confirms the previous structure determination in the space group P21nm, which was based on X-ray powder data [Suzuki, Ohtani & Kamada (2000). Phys. Chem. Miner. 27, 689–693]. The present study includes the determination of the H-atom parameters, which revealed a strong asymmetric hydrogen bond with an O⋯O distance of 2.5479 (12) Å. The δ-AlOOH structure is isotypic with that of β-CrOOH and may be considered as a distorted rutile type with all atoms located on mirror planes.