二氧化酸:很容易在实验中产生,但很难在理论上描述
M Brönstrup1, D Schröder, I Kretzschmar
1Institut für Organische Chemie, Technischen Universität Berlin, Strasse des 17. Juni 135, D-10623 Berlin, Germany.
Journal of the American Chemical Society
|March 29, 2001
概括
产生了一种二氧化阳离子,[Pt,O2](+),发现它具有高度反应性,能够激活像H2和CO这样的惰性分子. 这种反应性使催化转化成为可能,但导致大多数基质的选择性较差.
科学领域:
- 气相无机化学 气相无机化学
- 催化剂是一种催化剂.
- 计算化学是一种计算化学.
背景情况:
- 离子是各种催化过程中的关键.
- 了解-氧物种的反应性对于催化剂设计至关重要.
研究的目的:
- 为了生成和表征(V) 二氧化离子,[Pt,O2](+).
- 为了研究其对各种中性基质的反应性.
- 探索其在催化应用中的潜力,并了解其电子结构.
主要方法:
- 通过与N2O氧化Pt(+) 来产生气相离子.
- 用可氧化和惰性中性分子进行反应性研究.
- 广泛的初始计算研究分析结构特征和最低能耗.
主要成果:
- 成功生成了[Pt,O2](+) 离子,并被确定为OPtO(+) 结构.
- 它具有很高的反应性,可以激活惰性分子 (H2,CO,CH4) 并作为攻击性试剂.
- 证明了CO + N2O --> CO2 + N2转换的催化循环,PtOn+ (n=0-2) 的高转换数 (>100).
- 高反应性导致大多数基质的选择性差,例如,乙氧化产生了10个产品通道.
- Ab initio方法准确地描述了系统,而DFT的准确性较低.
结论:
- 二氧化阳离子 ([Pt,O2](+)) 具有明显的OPtO(+) 结构,具有显著的反应性.
- 它的侵略性对激活具有挑战性的基质充满希望,但限制了选择性.
- 计算方法对于理解这种反应性物种至关重要,在这种系统中,ab initio方法比DFT更准确.
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