Medvedev S A, Trojan I A, Eremets M I, Palasyuk T, Klapötke T M, Evers J
Max-Planck-Institute for Chemistry, Postfach 3060, D-55020 Mainz, Germany. Institute für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität, D-55099 Mainz, Germany.
J Phys Condens Matter. 2009 May 13;21(19):195404. doi: 10.1088/0953-8984/21/19/195404. Epub 2009 Apr 16.
We studied lithium azide (LiN(3)) by x-ray diffraction and Raman spectroscopy at hydrostatic compression up to pressures above 60 GPa at room temperature. The results of x-ray diffraction analyses reveal the stability of the ambient-pressure C 2/m crystal structure up to the highest pressure. The pressure dependence of librational modes provides evidence for an order-disorder transition at low pressures (below 3 GPa), similar to the transition observed previously at low temperatures. The observed structure stability indicates that this transition is not associated with structural changes. The phase stability of LiN(3) is in contrast to that of sodium azide (which is isostructural at ambient pressure), for which a set of phase transitions has been reported at pressures below 50 GPa.
我们在室温下对叠氮化锂（LiN₃）进行了高达60 GPa以上静水压力的X射线衍射和拉曼光谱研究。X射线衍射分析结果表明，常压下的C 2/m晶体结构在最高压力下仍保持稳定。振动模式的压力依赖性为低压（低于3 GPa）下的有序-无序转变提供了证据，这与之前在低温下观察到的转变类似。观察到的结构稳定性表明，这种转变与结构变化无关。LiN₃的相稳定性与叠氮化钠（在常压下结构相同）相反，后者在低于50 GPa的压力下已报道了一系列相变。
