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Title: Crystal‐to‐Gel Transformation Stimulated by a Solid‐State E→Z Photoisomerization
Abstract

The molecule (E)‐(5‐(3‐anthracen‐9‐yl‐allylidene)‐2,2‐dimethyl‐[1,3] dioxane‐4,6‐dione) (EAYAD) undergoesEZphotoisomerization. In the solid state, this photoisomerization process can initiate a physical transformation of the crystal that is accompanied by a large volume expansion (ca. 10 times), loss of crystallinity, and growth of large pores. This physical change requires approximately 10 % conversion of theEisomer to theZisomer and results in a gel‐like solid with decreased stiffness that still retains its mechanical integrity. The induced porosity allows the expanding gel to engulf superparamagnetic nanoparticles from the surrounding liquid. The trapped superparamagnetic nanoparticles impart a magnetic susceptibility to the gel, allowing it to be moved by a magnetic field. The photoinduced phase transition, starting with a compact crystalline solid instead of a dilute solution, provides a new route for in situ production of functional porous materials.

 
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Award ID(s):
1810514
NSF-PAR ID:
10118053
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
58
Issue:
43
ISSN:
1433-7851
Page Range / eLocation ID:
p. 15429-15434
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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