Prediction of the Glass Transition Temperatures of Zeolitic Imidazolate Glasses through Topological Constraint Theory

Yongjian Yang; Collin J Wilkinson; Kuo-Hao Lee; Karan Doss; Thomas D Bennett; Yun Kyung Shin; Adri C T van Duin; John C Mauro

doi:10.1021/acs.jpclett.8b03348

Prediction of the Glass Transition Temperatures of Zeolitic Imidazolate Glasses through Topological Constraint Theory

J Phys Chem Lett. 2018 Dec 20;9(24):6985-6990. doi: 10.1021/acs.jpclett.8b03348. Epub 2018 Dec 3.

Authors

Yongjian Yang¹, Collin J Wilkinson¹, Kuo-Hao Lee¹, Karan Doss¹, Thomas D Bennett², Yun Kyung Shin³, Adri C T van Duin^{1

3}, John C Mauro¹

Affiliations

¹ Department of Materials Science and Engineering , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States.
² Department of Materials Science and Metallurgy , University of Cambridge , 27 Charles Babbage Road , CB3 0FS Cambridge , U.K.
³ Department of Mechanical and Nuclear Engineering , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States.

PMID: 30484656
DOI: 10.1021/acs.jpclett.8b03348

Abstract

A topological constraint model is developed to predict the compositional scaling of glass transition temperature ( T_g) in a metal-organic framework glass, a_gZIF-62 [Zn(Im_{2- x}bIm _x)]. A hierarchy of bond constraints is established using a combination of experimental results and molecular dynamic simulations with ReaxFF. The model can explain the topological origin of T_g as a function of the benzimidazolate concentration with an error of 3.5 K. The model is further extended to account for the effect of 5-methylbenzimidazolate, enabling calculation of a ternary diagram of T_g with a mixture of three organic ligands in an as-yet unsynthesized, hypothetical framework. We show that topological constraint theory is an effective tool for understanding the properties of metal-organic framework glasses.