一个光化学的开关,用于调整H2核自旋异构体的平衡混合物,作为温度的函数
Michael Frunzi1, Steffen Jockusch, Judy Y-C Chen
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Journal of the American Chemical Society
|August 17, 2011
概括
光化学反应使得在C70.70富勒烯内可实现对 (pH2) 和正 (oH2) 的转化. 这个过程利用了富勒.
科学领域:
- 摄影化学的使用.
- 材料科学 材料科学 材料科学
- 量子化学 是一个量子化学.
背景情况:
- 存在于两个核自旋异构体:准 (pH2) 和正 (oH2).
- 在pH2和OH2之间的相互转换通常是缓慢的,需要特定的催化剂.
- 富勒,如C60和C70,可以封装小分子,影响它们的特性.
研究的目的:
- 为了研究烯C70 (H2@C70) 中封装的pH2和OH2的光化学相互转换.
- 探索富勒激发三元体状态作为H2同位素转换的旋转催化剂的作用.
- 为了比较H2@C70的光化学行为与H2@C60.
主要方法:
- 使用光对H2@C70进行光激发,以产生富勒三重体状态.
- 温度依赖的研究分析pH2/oH2.2的平衡比率.
- 用光谱分析来监测H2同位素比率和富勒烯三重体状态寿命.
主要成果:
- 对H2@C70的光刺激成功诱导了pH2和OH2.2的光化学相互转换.
- 富勒C70三重体状态作为pH2/oH2转换的高效旋转催化剂.
- H2@C60没有显著的光解 pH2 / oH2 相互转换,与H2@C70相比,由于三重状态的寿命较短,H2@C60没有显著的光解 pH2 / oH2 相互转换.
结论:
- 通过光照照射,可以通过光化学控制C70内的pH2/oH2比率.
- 在H2@C70.中,C70的长三重状态寿命对于其作为自旋催化剂的有效性至关重要.
- 这项研究展示了一种用于操纵封装分子核自旋状态的新方法.
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