中国科学院大连化学物理研究所机构知识库
Advanced  
DICP OpenIR  > 中国科学院大连化学物理研究所  > 期刊论文
题名: Determination of the Hydrogen-Bonding Induced Local Viscosity Enhancement in Room Temperature Ionic Liquids via Femtosecond Time-Resolved Depleted Spontaneous Emission
作者: Ma, Xiaonan;  Yan, Linyin;  Wang, Xuefei;  Guo, Qianjin1;  Xia, Andong
刊名: JOURNAL OF PHYSICAL CHEMISTRY A
发表日期: 2011-07-14
DOI: 10.1021/jp202391m
卷: 115, 期:27, 页:7937-7947
收录类别: SCI
文章类型: Article
WOS标题词: Science & Technology ;  Physical Sciences
类目[WOS]: Chemistry, Physical ;  Physics, Atomic, Molecular & Chemical
研究领域[WOS]: Chemistry ;  Physics
英文摘要: The fluorescence depletion dynamics of Rhodamine 700 (R-700) molecules in room temperature ionic liquids (RTILs) 1-ethyl-3-methylimidazolium tetrafluoroborate ([emim][BF4]) and 1-hydroxyethyl-3-methylimidazolium tetrafluoroborate ([HOemim]-[BF4]) were investigated to determine the local viscosity of the microenvironment surrounding the fluorescent molecules, which is induced by strong hydrogen bonding interaction between cationic and anionic components in RTILs. The solvation and rotation dynamics of R-700 molecules in RTILs show slower time constants relative to that in conventional protic solvents with the same bulk viscosity, indicating that the probe molecule is facing a more viscous microenvironment in RTILs than in conventional solvents because of the strong hydrogen bonding interaction between cationic and anionic components. In addition, this effect is more pronounced in hydroxyl-functionalized ionic liquid than in the regular RTIL due to the presence of a hydroxyl group as a strong hydrogen bonding donor. The hydrogen-bonding-induced local viscosity enhancement effect related to the heterogeneity character of RTILs is confirmed by the nonexponential rotational relaxation of R-700 determined by time-correlated single photon counting (TCSPC). The geometry of hydrogen bonding complexes with different components and sizes are further optimized by density functional theory methods to show the possible hydrogen-bond networks. A model of the hydrogen-bonding network in RTILs is further proposed to interpret the observed specific solvation and local viscosity enhancement effect in RTILs, where most of the fluoroprobes exist as the free nonbonding species in the RTIL solutions and are surrounded by the hydrogen-bonding network formed by the strong hydrogen-bonding between the cationic and anionic components in RTIL. The optimized geometry of hydrogen bonding complexes with different components and sizes by density functional theory methods confirms the local viscosity enhancement effect deduced from fluorescence depletion and TCSPC experiments. The calculated interaction energies reveal the existence of the stronger hydrogen bonding network in RTILs (especially in hydroxyl-functionalized ionic liquid) than that in conventional protic solvent, which leads to the enhancement effect of local microviscosity, and therefore leads to the slow solvation and rotation dynamics of probe molecules observed in RTILs.
关键词[WOS]: SOLVENT-SENSITIVE FLUOROPHORE ;  SOLVATION DYNAMICS ;  ROTATIONAL RELAXATION ;  PHOTOPHYSICAL PROPERTIES ;  TRANSIENT ABSORPTION ;  SPECTRAL PROPERTIES ;  ELECTRON-TRANSFER ;  SOLUTE ROTATION ;  DYE MOLECULES ;  FLUORESCENCE
语种: 英语
WOS记录号: WOS:000292479800008
Citation statistics: 
内容类型: 期刊论文
URI标识: http://cas-ir.dicp.ac.cn/handle/321008/142294
Appears in Collections:中国科学院大连化学物理研究所_期刊论文

Files in This Item:

There are no files associated with this item.


作者单位: 1.Chinese Acad Sci, Inst Chem, State Key Lab Mol React Dynam, Beijing 100190, Peoples R China
2.Chinese Acad Sci, Inst Chem, BNLMS, Beijing 100190, Peoples R China

Recommended Citation:
Ma, Xiaonan,Yan, Linyin,Wang, Xuefei,et al. Determination of the Hydrogen-Bonding Induced Local Viscosity Enhancement in Room Temperature Ionic Liquids via Femtosecond Time-Resolved Depleted Spontaneous Emission[J]. JOURNAL OF PHYSICAL CHEMISTRY A,2011,115(27):7937-7947.
Service
 Recommend this item
 Sava as my favorate item
 Show this item's statistics
 Export Endnote File
Google Scholar
 Similar articles in Google Scholar
 [Ma, Xiaonan]'s Articles
 [Yan, Linyin]'s Articles
 [Wang, Xuefei]'s Articles
CSDL cross search
 Similar articles in CSDL Cross Search
 [Ma, Xiaonan]‘s Articles
 [Yan, Linyin]‘s Articles
 [Wang, Xuefei]‘s Articles
Related Copyright Policies
Null
Social Bookmarking
  Add to CiteULike  Add to Connotea  Add to Del.icio.us  Add to Digg  Add to Reddit 
所有评论 (0)
暂无评论
 
评注功能仅针对注册用户开放,请您登录
您对该条目有什么异议,请填写以下表单,管理员会尽快联系您。
内 容:
Email:  *
单位:
验证码:   刷新
您在IR的使用过程中有什么好的想法或者建议可以反馈给我们。
标 题:
 *
内 容:
Email:  *
验证码:   刷新

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.

 

 

Valid XHTML 1.0!
Powered by CSpace