Affiliation:
1. Department of Chemistry Graduate School of Engineering Science Osaka University Toyonaka Osaka 560‐8531 Japan
2. Department of Chemistry Graduate School of Science Osaka Metropolitan University Sumiyoshi‐ku Osaka Osaka 558‐8585 Japan
Abstract
AbstractA liquescent bis(malononitriledithiolato)nickel(III) complex with a bis(methoxyethyl)imidazolium cation, 1[Ni(mnt)2], exhibits three‐stage thermochromic modulation of transparency/absorption in the short‐wave‐infrared (SWIR) region (1000–2500 nm), driven by associated structural changes. Upon heating, the electronic spectra of 1[Ni(mnt)2] in the SWIR region shift to shorter wavelengths accompanying with the solid–liquid phase transition at 76 °C. Further heating to over 109 °C induces a second transition of the electronic spectra, characterized by a blue‐shift of the SWIR absorption in the liquid phase. The results of temperature‐dependent electronic spectra and magnetic susceptibility indicated that the thermochromic changes can be attributed to the two‐step dissociation of the associated structures of [Ni(mnt)2]−, occurring during the solid–liquid phase transition and the shift of dimer–monomer equilibrium in the liquid state. These changes can be visualized using an SWIR imaging camera under appropriate SWIR lights.
Funder
Tokyo Ohka Foundation for The Promotion of Science and Technology
Subject
Biomaterials,Biotechnology,General Materials Science,General Chemistry