Abstract
Crystal-structure prediction methods and diffraction data show that a newly discovered form of boron is partially ionic. This is the first time such a structure has been observed for any elemental solid. Boron is an element of fascinating chemical complexity. This arises from frustration: situated between metals and insulators in the periodic table, boron has only three valence electrons that could in principle favour metallicity, yet they are sufficiently localized to give rise to an insulating state. This delicately balanced electronic structure is easily modified by pressure, temperature and impurities, making it difficult to establish boron's structure and properties. Oganov et al. have now explored the high-pressure behaviour of boron and uncovered a previously unknown ionic phase consisting of negatively charged icosahedral B12 clusters and positively charged B2 pairs. The ionicity of the new phase strongly affects many of its properties, and arises from the different electronic properties of the B12 clusters and B2 pairs and the resultant charge transfer between them.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
