화학공학소재연구정보센터
Journal of the American Chemical Society, Vol.140, No.20, 6245-6248, 2018
Compression of a Flapping Mechanophore Accompanied by Thermal Void Collapse in a Crystalline Phase
Mechanical control of the molecular energy landscape is an important issue in modern materials science. Mechanophores play a unique role in that the mechanical responses are induced against the activation barrier for intramolecular transformation with the aid of external forces. Here we report an unprecedented activation process of a flexible flapping mechanophore. Namely, thermal void collapse in a crystalline phase triggers mechanophore compression in a definite proportion. Unfavored conformational planarization of the flapping mechanophore is compulsorily induced by packing force, leading to a total energy gain in crystal packing. Fluorescence chromism indicates extended pi conjugation resulting from the mechanophore compression, giving rise to an energy transfer from the unpressed to compressed conformers.