Alkali-metal-fulleride phase equilibria.
Alkali-metal-fulleride phase equilibria.
复制标题
碱金属富勒烯化物相平衡。
DOI：
--
复制
发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Weaver
中科院分区：
文献类型：
--
作者：
Poirier;Owens;Weaver
The binary phase diagrams of the alkali-metal fullerides, ${mathit{A}}_{mathit{x}}$${mathrm{C}}_{60}$, are discussed in light of recent experimental results concerning the ${mathit{A}}_{1}$${mathrm{C}}_{60}$ phases and their transformations. The ${mathrm{Rb}}_{1}$${mathrm{C}}_{60}$ and ${mathrm{Cs}}_{1}$${mathrm{C}}_{60}$ phases undergo diffusionless structural transformations upon cooling and their phase diagrams require solutions that differ from the eutectoid transformation of ${mathrm{K}}_{1}$${mathrm{C}}_{60}$. X-ray photoelectron spectroscopy has been used to characterize these transformations. Phase diagrams incorporating two invariant reactions are proposed. The equilibrium vapor pressure of ${mathrm{C}}_{60}$ has been determined at lower temperatures than prevously examined and the pure ${mathrm{C}}_{60}$ phase diagram has been assembled for a large range of temperature and pressure. The predicted effects of solid-solution formation on the fcc to simple cubic transition of ensuremath{alpha}-${mathrm{C}}_{60}$ are discussed in terms of eutectoid and peritectoid phase-diagram topologies. High-temperature decomposition with fractional sublimation has been used to gain insight into the relative thermal stabilities of the various compounds. Using this information and data from the literature, a ${mathrm{K}}_{mathit{x}}$${mathrm{C}}_{60}$ phase diagram extending to vaporization temperatures is proposed.
The binary phase diagrams of the alkali-metal fullerides, ${mathit{A}}_{mathit{x}}$${mathrm{C}}_{60}$, are discussed in light of recent experimental results concerning the ${mathit{A}}_{1}$${mathrm{C}}_{60}$ phases and their transformations. The ${mathrm{Rb}}_{1}$${mathrm{C}}_{60}$ and ${mathrm{Cs}}_{1}$${mathrm{C}}_{60}$ phases undergo diffusionless structural transformations upon cooling and their phase diagrams require solutions that differ from the eutectoid transformation of ${mathrm{K}}_{1}$${mathrm{C}}_{60}$. X-ray photoelectron spectroscopy has been used to characterize these transformations. Phase diagrams incorporating two invariant reactions are proposed. The equilibrium vapor pressure of ${mathrm{C}}_{60}$ has been determined at lower temperatures than prevously examined and the pure ${mathrm{C}}_{60}$ phase diagram has been assembled for a large range of temperature and pressure. The predicted effects of solid-solution formation on the fcc to simple cubic transition of ensuremath{alpha}-${mathrm{C}}_{60}$ are discussed in terms of eutectoid and peritectoid phase-diagram topologies. High-temperature decomposition with fractional sublimation has been used to gain insight into the relative thermal stabilities of the various compounds. Using this information and data from the literature, a ${mathrm{K}}_{mathit{x}}$${mathrm{C}}_{60}$ phase diagram extending to vaporization temperatures is proposed.