Thermodynamic description of condensed phases

摘要: Phases may be smaller than visible to the human eye. In order characterize a microphase, phase 1 μm, one must consider surface area and free energy in addition standard thermodynamic functions. As approaches nanometer sizes, also needs know changing functions within phases. The Gibbs–Thomson equation can used microphases, but not nanophases. For latter, glass transition is needed assess properties interior. classify condensed phases as liquid, solid, mesophase, or crystal, molecular motion structure. Most important are large-amplitude displacements form of translation, rotation, conformational motion. An operational definition based on experiments an updated classification given. surprising result observation that crystals, earlier assumed prime examples solids, have order–disorder transitions more mobile mesophases, well without change crystal structure, i.e., under certain condition, they cannot identified solid. To these observations, has add fact start gradually abrupt changes These observations limit usefulness 80-year-old being first second order. Quantitative thermal analysis shown tool identify possible total 57 different states terms their macroscopic structure