• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The Journal of Chemical Physics >Experimental and theoretical studies of rate coefficients for the reaction O(P-3)+CH3OH at high temperatures - art. no. 244314
【24h】

Experimental and theoretical studies of rate coefficients for the reaction O(P-3)+CH3OH at high temperatures - art. no. 244314

机译：O（P-3）+ CH3OH高温反应速率系数的实验和理论研究-艺术。没有。 244314

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

Rate coefficients of the reaction O(P-3)+CH3OH in the temperature range of 835-1777 K were determined using a diaphragmless shock tube. O atoms were generated by photolysis of SO2 with a KrF excimer laser at 248 nm or an ArF excimer laser at 193 nm; their concentrations were monitored via atomic resonance absorption excited by emission from a microwave-discharged mixture of O-2 and He. The rate coefficients determined for the temperature range can be represented by the Arrhenius equation, k(T)=(2.29 +/- 0.18)x10(-10) exp[-(4210 +/- 100)/T] cm(3) molecule(-1) s(-1); unless otherwise noted, all the listed errors represent one standard deviation in fitting. Combination of these and previous data at lower temperature shows a non-Arrhenius behavior described as the three-parameter equation, k(T)=(2.74 +/- 0.07)x10(-18)T(2.25 +/- 0.13) exp[-(1500 +/- 90)/T] cm(3)molecule(-1) s(-1). Theoretical calculations at the Becke-3-Lee-Yang-Parr (B3LYP)/6-311+G(3df,2p) level locate three transition states. Based on the energies computed with coupled clusters singles, doubles (triples) [CCSD(T)]/6-311+G(3df,2p)//B3LYP/6-311+G(3df,2p), the rate coefficients predicted with canonical variational transition state theory with small curvature tunneling corrections agree satisfactorily with the experimental observations. The branching ratios of two accessible reaction channels forming OH+CH2OH (1a) and OH+CH3O (1b) are predicted to vary strongly with temperature. At 300 K, reaction (1a) dominates, whereas reaction (1b) becomes more important than reaction (1a) above 1700 K. (c) 2005 American Institute of Physics.
机译：使用无隔膜激波管确定在835-1777 K温度范围内反应O（P-3）+ CH3OH的速率系数。 O原子是通过248 nm的KrF准分子激光或193 nm的ArF准分子激光对SO2进行光解而产生的;它们的浓度是通过原子共振吸收来监测的，该吸收是由O-2和He的微波放电混合物发射而激发的。在温度范围内确定的速率系数可以用Arrhenius方程表示，k（T）=（2.29 +/- 0.18）x10（-10）exp [-（4210 +/- 100）/ T] cm（3）分子（-1）s（-1）;除非另有说明，否则所有列出的误差均表示装配的一个标准偏差。这些数据和先前的数据在较低温度下的组合显示了一个非阿伦尼乌斯行为，描述为三参数方程，k（T）=（2.74 +/- 0.07）x10（-18）T（2.25 +/- 0.13）exp [ -（1500 +/- 90）/ T] cm（3）分子（-1）s（-1）。在Becke-3-Lee-Yang-Parr（B3LYP）/ 6-311 + G（3df，2p）级别进行的理论计算确定了三个过渡状态。基于耦合簇计算的能量，单，双（三重）[CCSD（T）] / 6-311 + G（3df，2p）// B3LYP / 6-311 + G（3df，2p），预测的速率系数具有典型曲率隧穿校正的典型变分过渡态理论与实验结果令人满意。预测形成OH + CH2OH（1a）和OH + CH3O（1b）的两个可及的反应通道的分支比会随温度强烈变化。在300 K时，反应（1a）占主导地位，而在1700 K以上时，反应（1b）变得比反应（1a）更重要。（c）2005年美国物理研究所。

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