Investigating pure vibrational dephasing of I3− in solution: Temperature dependence of T2* for the fundamental and first harmonic of ν1
| Autor: | Zhaohui Wang, Sanford Ruhman, Ronnie Kosloff, Jiri Vala, Erez Gershgoren |
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| Rok vydání: | 2003 |
| Předmět: |
education.field_of_study
Chemistry Overtone Dephasing Population Intermolecular force Relaxation (NMR) Analytical chemistry General Physics and Astronomy Atmospheric temperature range Spin–spin relaxation symbols.namesake symbols Physical and Theoretical Chemistry Atomic physics education Raman spectroscopy |
| Zdroj: | The Journal of Chemical Physics. 118:3660-3667 |
| ISSN: | 1089-7690 0021-9606 |
| DOI: | 10.1063/1.1539844 |
| Popis: | Pure ν1 vibrational dephasing of triiodide is recorded in ethanol and methyl-tetrahydrofurane solutions from 300 to 100 K, for the vibrational fundamental and its first overtone. Using impulsive Raman spectroscopy, dephasing is demonstrated to be homogeneous throughout the temperature range studied. Independent measures of T1 prove that population relaxation contributes negligibly to the dephasing rates. The reduction in temperature gradually leads to a ∼2-fold decrease in the rate of pure dephasing. With cooling the ratio of T2(n=1)*/T2(n=2)* reduces slightly but remains in the range of 2.7 to 2. These results are discussed in terms of Kubo lineshape and Poisson dephasing theories. Neither of these consistently explains the experimental observations assuming reasonable intensities and rates of intermolecular encounters in the solutions. |
| Databáze: | OpenAIRE |
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