在Cp*2Mo2S4复合体中为S-H债券的自由能源景观
Aaron M Appel1, Suh-Jane Lee, James A Franz
1Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, USA.
Journal of the American Chemical Society
|March 25, 2009
概括
这项研究量化了-硫复合物的热化学数据,揭示了与催化应用中的过渡金属化物可比的S-H键强度.
科学领域:
- 有机金属化学 有机金属化学
- 无机化学 无机化学 有机化学
- 催化剂是一种催化剂.
背景情况:
- -硫复合体表现出与催化有关的多种反应性.
- 了解这些复合物的热化学特性对于优化催化过程至关重要.
研究的目的:
- 为新型硫复合物提供一套广泛的热化学数据.
- 为了比较这些复合物的特性与过渡金属化物.
- 使用自由能源景观可视化复杂的稳定性.
主要方法:
- 电化学潜力的确定. 电化学潜力的确定.
- 酸度 (pK(a)) 的测量.
- 均质溶液键解离自由能 (SBDFEs) 和化物供体能力的计算.
主要成果:
- 获得了广泛的热化学数据:电化学电位 (+0.6至 -2.0V),pK (a) 值 (5至31),SBDFEs (43至68 kcal/mol) 和化物捐赠能力 (44至84 kcal/mol).
- 热化学参数与过渡金属化物可比.
- 创建了自由能量景观,以说明物种在不同pH和H2过压下的稳定性.
结论:
- 研究的Mo(2) S(4) 复合物作为同质和异质硫化物催化剂的有价值模型.
- 结果强调了这些复合体中SH键强度的显著可调性.
- 这项工作提供了有关催化剂的硫系统基本反应性的见解.
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