physica status solidi (a)
Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Editor: Stefan Hildebrandt (Editor-in-Chief), Sabine Bahrs (Deputy Editor)
Online ISSN: 1862-6319
X-ray absorption and EXAFS studies of Ge coordination and bonding in high-pressure nitrides: β-Ge3N4 (phenacite) and γ-Ge3N4 (spinel)
This issue's Editor's Choice by Craig L. Bull et al.  deals with structural investigations of the high-pressure phases and phase transitions of germanium nitride. The cover picture shows the low-pressure phenacite structure of β-Ge3N4. Ge atoms are in tetrahedral coordination, and N atoms are trigonally coordinated. During high pressure treatment, some of the N sites become distorted and approach the neighbouring Ge atoms, locally forming GeN5 units. During high pressure–high temperature synthesis, spinel-structured γ-Ge3N4 is eventually formed, containing GeN4 and GeN6 units.
Paul F. McMillan is Professor of Chemistry at University College London and at the Royal Institution. His research interests include high pressure synthesis and studies of new materials, open framework and nanocrystalline semiconductors, and polyamorphic transitions in glasses and liquids.
This issue also contains the Proceedings of the 4th German/Brazilian Workshop on Applied Surface Science, held at Ringberg Castle, Tegernsee, Germany, 21–26 September 2003. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)