Grzelak Adam, Gawraczyński Jakub, Jaroń Tomasz, Kurzydłowski Dominik, Budzianowski Armand, Mazej Zoran, Leszczyński Piotr J, Prakapenka Vitali B, Derzsi Mariana, Struzhkin Viktor V, Grochala Wojciech
Faculty of Chemistry, University of Warsaw , ul. Pasteura 1, 02-093 Warsaw, Poland.
Center of New Technologies, University of Warsaw , ul. Banacha 2C, 02-097 Warsaw, Poland.
Inorg Chem. 2017 Dec 4;56(23):14651-14661. doi: 10.1021/acs.inorgchem.7b02528. Epub 2017 Nov 15.
A combined experimental-theoretical study of silver(I) and silver(II) fluorides under high pressure is reported. For Ag, the CsCl-type structure is stable to at least 39 GPa; the overtone of the IR-active mode is seen in the Raman spectrum. Its AgF sibling is a unique compound in many ways: it is more covalent than other known difluorides, crystallizes in a layered structure, and is enormously reactive. Using X-ray diffraction and guided by theoretical calculations (density functional theory), we have been able to elucidate crystal structures of high-pressure polymorphs of AgF. The transition from ambient pressure to an unprecedented nanotubular structure takes place via an intermediate orthorhombic layered structure, which lacks an inversion center. The observed phase transitions are discussed within the broader framework of the fluorite → cotunnite → NiIn series, which has been seen for other metal difluorides.
报道了一项关于高压下氟化银（I）和氟化银（II）的实验与理论相结合的研究。对于银而言，氯化铯型结构至少在39吉帕的压力下是稳定的；红外活性模式的泛音出现在拉曼光谱中。它的氟化银同类物在许多方面都是独特的化合物：它比其他已知的二氟化物具有更强的共价性，以层状结构结晶，并且具有极高的反应活性。利用X射线衍射并在理论计算（密度泛函理论）的指导下，我们得以阐明氟化银高压多晶型物的晶体结构。从常压到前所未有的纳米管结构的转变是通过一个缺少对称中心的中间正交层状结构发生的。在萤石→方铊矿→镍铟系列这一更广泛的框架内讨论了观察到的相变，其他金属二氟化物也出现过该系列相变。
