Atomistic Models of Amorphous Metal-Organic Frameworks

TL;DR

This paper reviews methods for determining atomistic models of amorphous metal-organic frameworks, highlighting experimental and simulation techniques like RMC, CRN, molecular dynamics, and assembly algorithms.

Contribution

It provides a comprehensive comparison of existing methodologies for modeling the microscopic structure of amorphous MOFs using various experimental and computational approaches.

Findings

Comparison of experimental and simulation methods for amorphous MOFs

Overview of atomistic modeling techniques like RMC, CRN, MD, and assembly algorithms

Discussion of challenges in characterizing amorphous MOFs at the microscopic level

Abstract

There is an increasing interest in the amorphous states of metal-organic frameworks (MOFs) and porous coordination polymers, which can be produced by pressure-induced amorphization, temperature-induced amorphization, melt-quenching, ball-milling, irradiation, etc. They can exhibit useful physical and chemical properties, distinct from those achievable in the crystalline states, along with greater ease of processing, and intrinsic advantages over crystals and powders, such as high transparency and mechanical robustness. However, these amorphous states are particularly challenging to characterize, and the determination of their framework structure at the microscopic scale is difficult, with only indirect structural information available from diffraction experiments. In this Perspective, we review and compare the existing methodologies available for the determination of microscopic models of amorphous MOFs, based on both experimental data and simulation methods. In particular, we present the atomistic models that can be obtained using Reverse Monte Carlo (RMC) methods, Continuous Random Networks (CRN), classical and \emph{ab initio} molecular dynamics, reactive force fields, and simulated assembly/polymerization algorithms.