Nitro–nitrito linkage isomerization is a well-known photochemical reaction of metal complexes in the solid state. To quantitatively elucidate the influence of the crystal environment on this reaction, we synthesized salts of a cationic platinum(II) nitrito complex with Pt(NO₂)₄^2– and (FSO₂)₂N^– anions (1-Pt(NO₂)₄ and 1-FSA, respectively). Their thermal properties and photoreactivities were investigated, and the linkage isomerization of the cations and the Pt(NO₂)₄ anion upon ultraviolet photoirradiation at 180 K was observed by X-ray structural analysis. The isomerization levels for the cations in 1-Pt(NO₂)₄ and 1-FSA were 49% and 80%, respectively, and that for the Pt(NO₂)₄ anion was in the range of 0–65%. The conversion was correlated with the reaction cavity size surrounding the NO₂ ligands.

中文翻译：

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铂（II）与Pt（NO ₂）₄ ^2–和（FSO ₂）₂ N ^–阴离子的配合物的硝基硝基光致异构化：异构化率与反应腔之间的关系

硝化腈键异构化是固态金属配合物的光化学反应。为了定量说明晶体环境对该反应的影响，我们合成了阳离子铂（II）亚硝基络合物与Pt（NO ₂）₄ ^2–和（FSO ₂）₂ N ^–阴离子（1-Pt（NO ₂）分别为₄和1-FSA）。研究了它们的热性质和光反应性，以及阳离子和Pt（NO ₂）₄的键合异构化通过X射线结构分析观察到在180K的紫外线下的阴离子。1-Pt（NO ₂）₄和1-FSA中阳离子的异构化程度分别为49％和80％，Pt（NO ₂）₄阴离子的异构化程度为0-65％。该转化率与围绕NO ₂配体的反应腔尺寸相关。