The optimization and modulation of the properties of photochromic compounds, such as their activation wavelengths and thermal relaxation half‐lives (τ_1/2), are essential for their adaptation in various applications. In this work, we studied the effect of co‐planarization of the rotary fragment of two photochromic hydrazones with the core of the molecule on their switching properties. The Z and E isomers of both compounds exhibit red‐shifted absorption bands relative to their twisted versions, allowing for their photoswitching using longer wavelengths of light. Additionally, the thermal half‐lives of both hydrazones are drastically shortened from hundreds of years to days.

中文翻译：

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腙光电开关中平坦化引起的激活波长红移和热半衰期加速。

光致变色化合物特性的优化和调制，例如它们的激活波长和热弛豫半衰期（τ _1/2），对于它们适应各种应用至关重要。在这项工作中，我们研究了两个光致变色腙的旋转片段与分子核心的共平面化对其开关特性的影响。两种化合物的Z和E异构体相对于它们的扭曲版本表现出红移吸收带，允许它们使用更长波长的光进行光切换。此外，两种腙的热半衰期都从数百年大幅缩短至几天。