In this paper, mechanoresponsive fluorescent molecules with high “off–on” contrast ratios that undergo molecular packing transformation from amorphous phase to crystalline by scratching are first reported. Three 2-aminobenzophenone derivatives 1, 2, and 3, which possess crystallization-induced fluorescence characteristics, exhibited bright cyan, blue, and green fluorescence colors with “off–on” contrast ratios as high as 175-fold by scratching. The scratching induced transformation from amorphous phase to crystalline of 1, 2, and 3 were directly observed by XRD and SEM studies. In addition, the fluorescence of the scratched sample can readily convert back into the initial nonfluorescent state by fuming in ethanol or heating. Letters with three fluorescence emission colors of 1, 2, and 3 in ethanol solution smeared on a glass surface can be easily written by scratching and erased by fumigation, demonstrating the potential value as reversible mechanoresponsive fluorescent materials.

中文翻译：

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基于高“关-开”对比度的非晶相到结晶转变的2-氨基二苯甲酮衍生物的机械响应荧光

在本文中，首次报道了具有高“开-关”对比率的机械响应性荧光分子，该分子经历了从无定形相到划痕的结晶从分子相到分子的堆积。三个2氨基二苯甲酮衍生物1，2，和3，其具有结晶诱导的荧光特性，展出亮青色，蓝色，和绿色的荧光的颜色与“断-通”对比度一样高通过刮擦175倍。从非晶相刮擦诱导转化成结晶的1，2，和3通过XRD和SEM研究直接观察到。另外，通过在乙醇中发烟或加热，被划伤的样品的荧光可以很容易地转换回初始的非荧光状态。用三种荧光发光颜色的字母1，2，和3中涂在玻璃表面上的乙醇溶液可以通过刮擦容易地写和擦除熏蒸，展示的潜在价值为可逆mechanoresponsive荧光材料。