title: Softening upon Adsorption in Microporous Materials: A Counterintuitive Mechanical Response.
abstract: We demonstrate here that microporous materials can exhibit softening upon adsorption of guest molecules, at low to intermediate pore loading, in parallel to the pore shrinking that is well-known in this regime. This novel and counterintuitive mechanical response was observed through molecular simulations of both model pore systems (such as slit pore) and real metal-organic frameworks. It is contrary to common belief that adsorption of guest molecules necessarily leads to stiffening due to increased density, a fact that we show is the high-loading limit of a more complex behavior: a nonmonotonic softening-then-stiffening.
authors.affiliation: PSL Research University, Chimie ParisTech - CNRS, Institut de Recherche de Chimie Paris, 75005 Paris, France.
authors.forename: Félix
authors.initials: F
authors.lastname: Mouhat
authors.affiliation: École Normale Supérieure, PSL Research University, Département de Chimie, Sorbonne Universités - UPMC Univ Paris 06, CNRS, 75005 Paris, France.
authors.forename: David
authors.initials: D
authors.lastname: Bousquet
authors.affiliation: École Normale Supérieure, PSL Research University, Département de Chimie, Sorbonne Universités - UPMC Univ Paris 06, CNRS, 75005 Paris, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Boutin
authors.affiliation: PSL Research University, Chimie ParisTech - CNRS, Institut de Recherche de Chimie Paris, 75005 Paris, France.
authors.forename: Lila
authors.initials: L
authors.lastname: Bouëssel du Bourg
authors.affiliation: PSL Research University, Chimie ParisTech - CNRS, Institut de Recherche de Chimie Paris, 75005 Paris, France.
authors.forename: François-Xavier
authors.initials: FX
authors.lastname: Coudert
authors.affiliation: PSL Research University, Chimie ParisTech - CNRS, Institut de Recherche de Chimie Paris, 75005 Paris, France.
authors.forename: Alain H
authors.initials: AH
authors.lastname: Fuchs
mesh_terms: D000327:Adsorption; D056004:Molecular Dynamics Simulation; D009010:Monte Carlo Method; D009942:Organometallic Compounds / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D013499:Surface Properties
chemical_list: D009942:Organometallic Compounds
keywords: adsorption−deformation coupling; metal−organic frameworks; microporous materials; zeolitic imidazolate frameworks