Storm Christian V, Racioppi Stefano, Duff Matthew J, McHardy James D, Zurek Eva, McMahon Malcolm I
SUPA, School of Physics and Astronomy, and Centre for Science at Extreme Conditions, The University of Edinburgh, Edinburgh, UK.
Department of Chemistry, State University of New York at Buffalo, Buffalo, NY USA.
Commun Mater. 2025;6(1):201. doi: 10.1038/s43246-025-00925-w. Epub 2025 Sep 1.
The transparent 4 phase of dense sodium (Na), stable above 200 GPa, has been computed to be an electride in which valence electrons are localised on interstitial lattice sites within the structure. However, there is no experimental evidence for this interstitial electron localisation in Na, or indeed in other high-density electride phases. Using static compression and single-crystal X-ray diffraction techniques, we have grown and studied a single-crystal sample of Na in the 4 phase at 223 GPa. Using atomic form factors for 4-Na derived from quantum crystallography techniques, we present experimental results to support the electride nature of this phase.
致密钠的透明4相在200吉帕以上稳定，经计算它是一种电子化合物，其中价电子定域于结构内的间隙晶格位置上。然而，在钠中，甚至在其他高密度电子化合物相中，都没有这种间隙电子定域的实验证据。利用静态压缩和单晶X射线衍射技术，我们在223吉帕下生长并研究了处于4相的钠的单晶样品。利用从量子晶体学技术得出的4-Na的原子形状因子，我们给出了实验结果以支持该相的电子化合物性质。
