Phase Transitions and Polymerization of C6H6–C6F6 Cocrystal under Extreme Conditions

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• 作者：Yajie Wang ; Lijuan Wang ; Haiyan ZhengKuo Li ; Michał Andrzejewski ; Takanori Hattori ; Asami Sano-Furukawa ; Andrzej Katrusiak ; Yufei MengFuhui Liao ; Fang Hong ; Ho-kwang Mao
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：December 29, 2016
• 年：2016
• 卷：120
• 期：51
• 页码：29510-29519
• 全文大小：777K
• ISSN：1932-7455

文摘

Pressure-induced polymerization (PIP) of aromatic molecules can generate saturated carbon nanostructures. As a strongly interacted π–π stacking unit, the C₆H₆–C₆F₆ adduct is widely applied in supramolecular chemistry, and it provides a good preorganization for the PIP. Here we investigated the structural variation of C₆H₆–C₆F₆ cocrystal and the subsequent PIP process under high pressure. Four new molecular-complex phases V, VI, VII, and VIII have been identified and characterized by the in situ Raman, IR, synchrotron X-ray, and neutron diffraction. The phase V is different from the phases observed at low temperature, which has a tilted column structure. Phases VI and VII have a structure similar to phase V. Phase VIII polymerizes irreversibly upon compression above 25 GPa without any catalyst, producing sp³(CH/F)_n materials. The π–π interaction is still dominant below 0.5 GPa but is most likely to be overstepped under further compression, which is important for discussing the supramolecular phase transition and the polymerization process.