• 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 >Valence transitions of Br-2 in Ar matrices: Interaction with the lattice and predissociation
【24h】

Valence transitions of Br-2 in Ar matrices: Interaction with the lattice and predissociation

机译：Ar矩阵中Br-2的价态跃迁：与晶格的相互作用和预离解

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

Fluorescence spectra from v'=0 of the B, A and A' states of Br-2/Ar are presented for excitation wavelengths from 630 to 540 nm with high resolution, to evaluate isotopic splittings in emission and absorption. The observed progression of sharp zero phonon lines (ZPLs) from v'=2 to v'=19 in B excitation is used to derive spectroscopic constants. The ZPL broadening and the growing phonon sideband (PSB) contributions indicate an increase of matrix influence on the X-B transition with rising v'. Contributions of the PSB are parameterized with the Huang-Rhys coupling constant S, where S=1 near the potential minimum reflects the electron-phonon coupling and S=4 close to Franck-Condon maximum originates from vibrational coupling. The PSB spectral composition correlates with the matrix phonon density of states, and the ZPL broadens and shifts with temperature. Two crossings with repulsive states (between v'=4-5 and v'=7-9) leading to matrix induced predissociation and a third tentative one between v'=14 and 15 are indicated by ZPL broadening, population flow, and spectral shifts. The crossing energies are close to gas phase and matrix calculations. The stepwise flow of intensity from B via repulsive states to A' and, similarly, from the A continuum to A' is discussed. Emission quantum efficiency of the B state decreases from near unity at v'=0 to less than 10(-3) at v'=19. Broadening of ZPL near crossings yields predissociation times of 5 and 2.5 ps corresponding to probabilities of 5% and 10% per round-trip for the two lowest crossings, respectively. (c) 2008 American Institute of Physics.
机译：给出了从630至540 nm的激发波长具有高分辨率的Br-2 / Ar B，A和A'态的v'= 0的荧光光谱，以评估同位素在发射和吸收方面的分裂。在B激发中观察到的尖锐的零声子线（ZPL）从v'= 2到v'= 19的进程用于导出光谱常数。 ZPL的扩展和声子边带（PSB）的增加表明随着v'的增加，矩阵对X-B跃迁的影响增加。 PSB的贡献通过Huang-Rhys耦合常数S进行参数化，其中S = 1靠近电势最小值反映了电子-声子耦合，而S = 4接近Franck-Condon最大值源自振动耦合。 PSB频谱组成与状态的矩阵声子密度相关，并且ZPL随着温度变宽和移动。 ZPL拓宽，种群流动和光谱位移表示两次排斥相交（在v'= 4-5和v'= 7-9之间）导致基质诱导的预离解，第三次试探性在v'= 14和15之间。 。交叉能接近气相和矩阵计算。讨论了强度从B经由排斥状态到A'以及类似地从A连续体到A'的逐步流动。 B态的发射量子效率从v'= 0处的近似单位减小到v'= 19处的小于10（-3）。 ZPL在交叉口附近变宽会产生5 ps和2.5 ps的预解离时间，分别对应两个最低交叉点每次往返的概率分别为5％和10％。 （c）2008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