Liquid and Glass Phases of an Alkylguanidinium Sulfonate Hydrogen-Bonded Organic Framework
Adam H. Slavney, Hong Ki Kim, Songsheng Tao, Mengtan Liu, Simon J. L. Billinge, Jarad A. Mason
Abstract
Glassy phases of framework materials feature unique and tunable properties that are advantageous for gas separation membranes, solid electrolytes, and phase-change memory applications. Here, we report a new guanidinium organosulfonate hydrogen-bonded organic framework (HOF) that melts and vitrifies below 100 °C. In this low-temperature regime, non-covalent interactions between guest molecules and the porous framework become a dominant contributor to the overall stability of the structure, resulting in guest-dependent melting, glass, and recrystallization transitions. Through simulations and X-ray scattering, we show that the local structures of the amorphous liquid and glass phases resemble those of the parent crystalline framework.