Mechano-responsive color changes of a Pt(ii) complex possessing triethylene glycol towards pressure sensors†

Mechanochromic molecules have attracted significant attention owing to their potential in the development of pressure sensors. However, relatively few studies have investigated the detailed mechanisms of the mechano-responsive nature and the quantitative visualization of mechanical forces. Herein, we report a square-planar platinum complex possessing triethylene glycol chains that exhibits mechanocromic behavior in the amorphous phase. Its mechanochromic nature was established using a combination of spectroscopic techniques, powder X-ray diffraction analyses, and computational chemistry techniques. The continuous changes in emission intensity allowed the platinum complex to be used as a mechanical force sensor, where the output signals were readable using a luminescence spectrometer. These findings demonstrate the potential benefits of square-planar platinum complexes and triethylene glycol chains for the creation of mechanochromic material.