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Title: A Ligand Field Molecular Mechanics Study of CO 2 ‐Induced Breathing in the Metal–Organic Framework DUT‐8(Ni)
Abstract

Flexible metal–organic Frameworks (MOFs) are an interesting class of materials due to their diverse properties. One representative of this class is the layered‐pillar MOF DUT‐8(Ni). This MOF consists of Ni2paddle wheels interconnected by naphthalene dicarboxylate linkers and dabco pillars (Ni2(ndc)2(dabco), ndc = 2,6‐naphthalene–dicarboxylate, dabco = 1,4‐diazabicyclo‐[2.2.2]‐octane). DUT‐8(Ni) undergoes a volume change of over 140% upon adsorption of guest molecules. Herein, a ligand field molecular mechanics (LFMM) study of the CO2‐induced flexibility of DUT‐8(Ni) is presented. LFMM is able to reproduce experimental and DFT structural features as well as properties that require large simulation cells. It is shown that the transformation energy from a closed to open state of the MOF is overcompensated fivefold by the host–guest interactions. Structural characteristics of the MOF explain the shape of the energy profile at different loading states and provide useful insights to the interpretation of previous experimental results.

 
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Award ID(s):
1704063
NSF-PAR ID:
10459325
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Theory and Simulations
Volume:
2
Issue:
11
ISSN:
2513-0390
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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