标题： 硼：寻找超硬多形体 显示英文标题

标题： Boron: a Hunt for Superhard Polymorphs

摘要： 硼是一种独特的元素，它是唯一一种所有已知的同素异形体都是超硬的元素，且其所有晶体结构都与其他任何元素的结构不同。 硼中的电子缺乏键合解释了它对即使是很小浓度的杂质原子也表现出显著的敏感性，并使硼能够与性质非常不同的元素形成奇特的化合物。 这些复杂性使得硼的研究成为一个巨大的挑战，在科学史上也形成了一个独特而有教育意义的篇章。 尽管听起来有些奇怪，1808年发现硼时却存在歧义，直到20世纪50年代至70年代才确立了纯硼的同素异形体，而直到2007年才确定了常压下的稳定相。 本文综述了从硼的发现到最新关于该元素相图、β-硼的结构和稳定性以及新高压同素异形体γ-硼的确立等研究历史。 显示英文摘要

摘要： Boron is a unique element, being the only element, all known polymorphs of which are superhard, and all of its crystal structures are distinct from any other element. The electron-deficient bonding in boron explains its remarkable sensitivity to even small concentrations of impurity atoms and allows boron to form peculiar chemical compounds with very different elements. These complications made the study of boron a great challenge, creating also a unique and instructive chapter in the history of science. Strange though it may sound, the discovery of boron in 1808 was ambiguous, with pure boron polymorphs established only starting from the 1950s-1970s, and only in 2007 was the stable phase at ambient conditions determined. The history of boron research from its discovery to the latest discoveries pertaining to the phase diagram of this element, the structure and stability of beta-boron, and establishment of a new high-pressure polymorph, gamma-boron, is reviewed.