Crystal Structure of Rb4C60 and K4C60 under Pressure

Ashfia Huq; Peter W. Stephens

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arXiv · cond-mat/0601425

Crystal Structure of Rb4C60 and K4C60 under Pressure

Ashfia Huq·Peter W. Stephens

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Abstract

We show that Rb_4C_60 transforms from its ambient pressure orientationally disordered tetragonal structure to an ordered orthorhombic structure (isostructural to Cs_4C_60) at or above 0.4 GPa. This opens the possibility of studying the previously observed metal-insulator transition under pressure in this narrow band system as a function of a continuous variable, rather than formulating distinct models for conducting and insulating fullerides. No such transition is observed in K_4C_60 to 2.0 GPa

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Ashfia Huq, Peter W. Stephens. 2006-01-18. Crystal Structure of Rb4C60 and K4C60 under Pressure. https://arxiv.org/abs/cond-mat/0601425

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