Sui Qi, Yang Ning-Ning, Gong Teng, Li Peng, Yuan Ye, Gao En-Qing, Wang Lin
Shanghai Key Laboratory of Green Chemistry and Chemical Processes, College of Chemistry and Molecular Engineering, East China Normal University , Shanghai 200062, People's Republic of China.
Center for High Pressure Science and Technology Advanced Research , Shanghai 201203, People's Republic of China.
J Phys Chem Lett. 2017 Nov 2;8(21):5450-5455. doi: 10.1021/acs.jpclett.7b02452. Epub 2017 Oct 25.
Stimuli-induced solid-state electron transfer (ET) underlies the use of viologen compounds as responsive materials, but unequivocal structure-property correlations for solid-state ET are still lacking. With different pseudopolymorphic solids derived from N,N'-bis(4-carboxylphenyl)viologen ([HbcpV]), here we report a systematic study on photo- and piezochromic properties associated with ET. We show that the higher the water content in the lattice, the less sensitively the compounds respond to light and pressure. It is proposed that the lattice water does not act as an electron donor but serves to change the ET energetics through its unique polarity and hydrogen bonding capability. The impedimental impact of water on solid-state ET of viologen compounds has not yet been recognized and elucidated prior to this work. The study also suggests that pressure is more powerful than light in inducing ET.
刺激诱导的固态电子转移（ET）是紫精化合物作为响应材料应用的基础，但固态ET明确的结构-性质相关性仍然缺乏。通过由N,N'-双(4-羧基苯基)紫精（[HbcpV]）衍生出的不同假多晶型固体，我们在此报告了一项关于与ET相关的光致变色和压致变色性质的系统研究。我们表明，晶格中的水含量越高，化合物对光和压力的响应就越不敏感。有人提出，晶格水不作为电子供体，而是通过其独特的极性和氢键能力来改变ET能量学。在这项工作之前，水对紫精化合物固态ET的阻碍作用尚未得到认识和阐明。该研究还表明，在诱导ET方面，压力比光更有效。
