0
Facebook
Latest News
Web Date: July 17, 2008

Gold Complex Changes Color Reversibly

Grinding and exposure to solvents trigger phase transformations and color changes
Department: Science & Technology
News Channels: JACS In C&EN
Credit: Hokkaido University
Credit: © 2008 J. Am. Chem. Soc.
8629news6
 
Credit: © 2008 J. Am. Chem. Soc.

Video

Reversible Photoluminescence

Gentle grinding of a new Au(I) complex in solid form changes its luminescence behavior, Japanese researchers report. UV light reveals the induced change in the compound as it goes from blue to yellow (a). The color change, which isn't apparent in visible light (b), can be reversed by exposing the fully ground powder (c) to drops of dichloromethane or other solvents (d). Powder turned completely blue by solvent (e) reverts to yellow after the solvent evaporates and the solid is again ground with a pestle (f).

Chemists Hajime Ito, Masaya Sawamura, and colleagues at Hokkaido University, in Sapporo, detected no degradation in luminescence even after 20 cycles of blue-to-yellow conversion of the [(C6F5Au)2(μ-1,4-diisocyanobenzene)] complex (J. Am. Chem. Soc., DOI: 10.1021/ja8019356).

X-ray and IR studies suggest that grinding transforms the more stable crystalline blue phase into an amorphous yellow phase and alters the coordination of the isocyanide ligands to the gold atoms. Such compounds could be used in recording and sensing devices, the authors propose.

 
Chemical & Engineering News
ISSN 0009-2347
Copyright © American Chemical Society