Abstract The viologen moiety has been widely used to endow complexes with chromic properties. In this work, we report three complexes Co(CMbpy)(H2O)5·BTC (1), Ni(CMbpy)(BTC)(H2O)4·5H2O (2), [Zn(CMbpy)(HBTC)(H2O)·(H2BTC)·3H2O]n (3) based on a viologen-derived ligand 1-(1-cyclohexylmethane)-4,4′-bipyridinium bromide (CMbpyBr) and 1,3,5-benzenetricarboxylic acid (H3BTC) by varying different metal ions, which endow these complexes with different structures and chromic properties. Of the three complexes, only 3 exhibits photochromism due to the generation of viologen radicals by photoinduced electron transfer. The reason why 1 and 2 cannot perform photochromism can be related to the slightly longer ET distance and the weaker electron-withdrawing ability of Co(II) and Ni(II). In contrast, complexes 1 and 2 exhibit irreversible hydrochromism due to the d-d transition in the ligand field observed by dehydration. This work provides new strategies for developing different responsive materials.

中文翻译：

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三种基于 1-(1-环己基甲烷)-4,4'-联吡啶的配合物的金属依赖性结构和响应

摘要 紫罗碱部分已被广泛用于赋予复合物变色特性。在这项工作中，我们报告了三种配合物 Co(CMbpy)(H2O)5·BTC (1)、Ni(CMbpy)(BTC)(H2O)4·5H2O (2)、[Zn(CMbpy)(HBTC)(H2O) ·(H2BTC)·3H2O]n (3) 基于紫精衍生配体 1-(1-环己基甲烷)-4,4'-溴化联吡啶 (CMbpyBr) 和 1,3,5-苯三甲酸 (H3BTC)不同的金属离子，赋予这些配合物不同的结构和铬特性。在这三种配合物中，由于光致电子转移产生紫罗碱自由基，只有 3 种表现出光致变色。1和2不能进行光致变色的原因可能与Co(II)和Ni(II)的ET距离稍长和吸电子能力较弱有关。相比之下，由于脱水观察到的配体场中的 dd 转变，配合物 1 和 2 表现出不可逆的水致变色。这项工作为开发不同的响应材料提供了新的策略。