du Bourg, Lila Bouessel; Ortiz, Aurelie U.; Boutin, Anne; Coudert, Francois-Xavier
Thermal and mechanical stability of zeolitic imidazolate frameworks polymorphs
APL MATERIALS, 2 Art. No. 124110, DEC 2014

Theoretical studies on the experimental feasibility of hypothetical Zeolitic Imidazolate Frameworks (ZIFs) have focused so far on relative energy of various polymorphs by energy minimization at the quantum chemical level. We present here a systematic study of stability of 18 ZIFs as a function of temperature and pressure by molecular dynamics simulations. This approach allows us to better understand the limited stability of some experimental structures upon solvent or guest removal. We also find that many of the hypothetical ZIFs proposed in the literature are not stable at room temperature. Mechanical and thermal stability criteria thus need to be considered for the prediction of new MOF structures. Finally, we predict a variety of thermal expansion behavior for ZIFs as a function of framework topology, with some materials showing large negative volume thermal expansion. (C) 2014 Author(s).


Find full text with Google Scholar.