A new interpretation of the meaning of the center of line slope from a two-dimensional infrared spectrum
A new interpretation of the meaning of the center of line slope from a two-dimensional infrared spectrum
复制标题
DOI：
10.1063/1.4953848
复制
发表时间：
2016-06-21
影响因子：
4.4
通讯作者：
Falvo, Cyril
中科院分区：
文献类型：
--
作者：
Falvo, Cyril
二维（2D）红外光谱的单个峰的斜率和频率-频率相关函数。这种近似超越了短时近似，通过引入一个时间参数来分离快波动和慢波动，从而包含了明确的纯退相机制。而在短时间近似下，线斜率的中心由归一化的频率波动自相关函数给出，我证明了使用这种新的近似，线斜率的中心在长时间尺度上测量一个移动和缩放的相关函数。结果提出了一个新的解释线斜率的中心的含义，允许更好地理解什么2D实验可以测量。为了说明这些发现，我比较这种近似与短时间近似的频率-频率相关函数的几个例子。我也给一个简单的指数衰减的相关函数的时间分离参数的值的估计。出版社：AIP Publishing
slope from a single peak of a two-dimensional (2D) infrared spectrum and the frequency-frequency correlation function. This approximation which goes beyond the short-time approximation includes explicitly pure dephasing mechanisms by introducing a time parameter that separates the fast fluctuations and slow fluctuations. While in the short-time approximation, the center of line slope is given by the normalized frequency fluctuations auto-correlation function, I show using this new approximation that the center of line slope measures on long time scales a shifted and scaled correlation function. The results present a new interpretation of the meaning of the center of line slope that allows for a better understanding of what 2D experiments can measure. To illustrate these findings, I compare this approximation with the short-time approximation for several examples of frequency-frequency correlation functions. I also give an estimate of the value of the time separation parameter for a correlation function with a simple exponential decay. Published by AIP Publishing.