• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Correlations between the Heat of Adsorption and the Position of the Center of the D-Band: Differences between Computation and Experiment
【24h】

Correlations between the Heat of Adsorption and the Position of the Center of the D-Band: Differences between Computation and Experiment

机译：吸附热与D波段中心位置之间的相关性：计算与实验之间的差异

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Previous DFT computations have shown that there should be a correlation between the calculated heat of adsorption of gases such as hydrogen, carbon monoxide, and ethylene and the energy of the center of the d-band. This paper considers whether the trends expected from the calculations agree with the available data. It is found that experimental heats of adsorption of CO on platinum single crystals increase linearly with increases in the energy of the center of the d-band as expected theoretically, but the slope is about one-third of that expected theoretically. Experimental heats of adsorption of hydrogen on platinum show a small decrease as the energy of the center of the d-band becomes less negative. By comparison, recent DFT calculations suggest a substantial increase. Experimental heats of adsorption of ethylene on platinum also show a small decrease as the energy of the center of the d-band becomes less negative. By comparison, recent DFT calculations suggest a substantial increase. Interestingly, the heat of adsorption of oxygen, and the heat of dissociative adsorption of ethylene, do follow the trends expected from the model, although no quantitative comparison is possible. Overall, calculated and experimental heats of adsorption differ by as much as 90 kJ/mol. Ours is the fifth recent paper that shows significant differences between careful experiments and careful DFT calculations. We suggest, therefore, that the functionals used to model adsorption need improvement.
机译：先前的DFT计算表明，所计算出的诸如氢，一氧化碳和乙烯等气体的吸附热与d波段中心的能量之间应该存在相关性。本文考虑了计算预期的趋势是否与可用数据一致。发现理论上如预期的那样，CO在铂单晶上的吸附吸附热随着d波段中心能量的增加而线性增加，但斜率约为理论上预期的三分之一。氢在铂上的吸附实验表明，随着d谱带中心能量的负负变小，其热降低很小。相比之下，最近的DFT计算表明有实质性的增长。随着d谱带中心能量的负负变小，乙烯在铂上的吸附实验热也显示出较小的下降。相比之下，最近的DFT计算表明有实质性的增长。有趣的是，尽管无法进行定量比较，但氧的吸附热和乙烯的解离吸附热的确符合模型的预期趋势。总体而言，计算得出的吸附热和实验吸附热相差多达90 kJ / mol。我们的第五篇论文显示了仔细的实验​​与仔细的DFT计算之间的显着差异。因此，我们建议用于建模吸附的功能需要改进。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号