The results of studies on negative photochromism of compounds and systems have been analyzed for the first time. It has been shown that the majority of studies deal with photochromic spiro compounds (spiropyrans and spirooxazines) whose negative photochromism is caused mainly by molecular structure, polarity and acidity of the medium, and complexation with metal ions. Among other most studied compounds, negative photochromism has been observed for photochromic dihydropyrenes. Photoisomerization of certain compounds, in particular, thioindigoid dyes, provides a photoinduced hypsochromic shift of absorption bands with substance color change.

中文翻译：

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有机系统中的负光致变色

化合物和系统的负光致变色研究的结果已首次进行了分析。研究表明，大多数研究涉及光致变色螺化合物（螺吡喃和螺恶嗪），其负光致变色主要由介质的分子结构，极性和酸度以及与金属离子的络合引起。在其他研究最多的化合物中，对于光致变色二氢hydro，已观察到负光致变色现象。某些化合物，特别是硫靛类染料的光致异构化，随着物质颜色的变化，提供了吸收带的光致变色移。