Two-dimensional infrared spectroscopy and ultrafast anisotropy decay of water
Two-dimensional infrared spectroscopy and ultrafast anisotropy decay of water
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DOI：
10.1063/1.3454733
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发表时间：
2010-06-14
影响因子：
4.4
通讯作者：
Skinner, J. L.
中科院分区：
文献类型：
--
作者：
Jansen, T. L. C.;Auer, B. M.;Skinner, J. L.
我们引入了一个稀疏矩阵算法，允许在许多耦合发色团的系统中的二维红外（2D）光谱的模拟。我们将该方法应用于散装水，我们的结果是基于最近开发的从头算振动哈密顿映射。理论和实验之间的定性协议被发现的2D光谱没有使用任何拟合或缩放参数的哈密顿量。计算的光谱散装水是没有那么不同的HOD在D2 O，我们可以理解，考虑在这两种情况下的光谱扩散时间相关函数。我们还计算了超快各向异性衰减，这是占主导地位的布居转移，发现与实验非常吻合。最后，我们确定了振动激发扩散速率，它比水分子本身的扩散快两个数量级以上。(C)2010年美国物理学会。[doi：10.1063/1.3454733]
We introduce a sparse-matrix algorithm that allows for the simulation of two-dimensional infrared (2DIR) spectra in systems with many coupled chromophores. We apply the method to bulk water, and our results are based on the recently developed ab initio maps for the vibrational Hamiltonian. Qualitative agreement between theory and experiment is found for the 2DIR spectra without the use of any fitting or scaling parameters in the Hamiltonian. The calculated spectra for bulk water are not so different from those for HOD in D2O, which we can understand by considering the spectral diffusion time-correlation functions in both cases. We also calculate the ultrafast anisotropy decay, which is dominated by population transfer, finding very good agreement with experiment. Finally, we determine the vibrational excitation diffusion rate, which is more than two orders of magnitude faster than the diffusion of the water molecules themselves. (C) 2010 American Institute of Physics. [doi:10.1063/1.3454733]