Lin Rong-Guang, Xu Gang, Lu Gang, Wang Ming-Sheng, Li Pei-Xin, Guo Guo-Cong
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , Fuzhou, Fujian 350002, People's Republic of China.
Inorg Chem. 2014 Jun 2;53(11):5538-45. doi: 10.1021/ic5002144. Epub 2014 May 20.
Two new member of (V)((2n+2)/2)[Bi(2n)Cl(8n+2)] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV(2+) = N,N'-dibenzyl-4,4'-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer Bi3Cl14 counterion. The novel in situ-synthesized symmetric viologen cation with aromatic groups on both sides of 4,4'-bipy would provide more opportunities to create π···π interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported viologen-metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the viologen dication, and the π···π interaction behaves as not only a powerful factor to stabilize the viologen monocation radical but also the second electron-transfer pathway, from a π-conjugated substituent to a viologen cation, for the photochromic process.
已获得(V)((2n + 2)/2)[Bi(2n)Cl(8n + 2)]系列杂化物的两个新成员，即(BzV)2[Bi2Cl10] (1)和(BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2)（其中BzV(2+) = N,N'-二苄基-4,4'-联吡啶鎓，(C6H5CH2)2O = 二苄基醚），化合物2含有前所未有的离散三聚体Bi3Cl14抗衡离子。在4,4'-联吡啶两侧带有芳香基团的新型原位合成对称紫精阳离子将为形成π···π相互作用以优化杂化物的光致变色性能提供更多机会，并且不同的铋卤化物低聚物使我们能够讨论该系列化合物中的尺寸效应。1和2均具有光致变色性，且它们的光响应速率比已报道的紫精-金属卤化物杂化物更快。实验和理论数据表明，无机低聚物的尺寸可显著影响紫精二价阳离子的光响应速率，并且π···π相互作用不仅是稳定紫精单阳离子自由基的重要因素，也是光致变色过程中从π共轭取代基到紫精阳离子的第二条电子转移途径。
