Mechanochromism and Polymorphism-Dependent Emission of Tetrakis(4-(dimethylamino)phenyl)ethylene

The
mechanochromic property of tetrakis­(4-(dimethylamino)­phenyl)­ethylene
(TDMAPE) with natural propeller shape and nearly centrosymmetric structure
was investigated. The destruction of the crystalline structure leads
to the planarization of molecular conformation, which is considered
as a possible reason for the red-shift of absorption and fluorescence
spectra after grinding. And the polymorphism-dependent emissions of
the two polymorphs of TDMAPE are mainly determined by the intramolecular
conformation, which show the increased coplanarity or conjugation
degree, ultimately leading to the bathochromic shift of the emissions.