Falvo Cyril, Palmieri Benoit, Mukamel Shaul
Department of Chemistry, University of California, Irvine, California 92697, USA.
J Chem Phys. 2009 May 14;130(18):184501. doi: 10.1063/1.3120771.
The two-dimensional vibrational response of the disordered strongly fluctuating OH exciton band in liquid water is investigated using a new simulation protocol. The direct nonlinear exciton propagation generalizes the nonlinear exciton equations to include nonadiabatic time dependent Hamiltonian and transition dipole fluctuations. The excitonic picture is retained and the large cancellation between Liouville pathways is built-in from the outset. The sensitivity of the photon echo and double-quantum-coherence techniques to frequency fluctuations, molecular reorientation, intermolecular coupling, and the two-exciton coherence is investigated. The photon echo is particularly sensitive to the frequency fluctuations and molecular reorientation, whereas the double-quantum coherence provides a unique probe for intermolecular couplings and two-exciton coherence.
利用一种新的模拟方法研究了液态水中无序且强烈波动的OH激子带的二维振动响应。直接非线性激子传播将非线性激子方程推广到包含非绝热含时哈密顿量和跃迁偶极子涨落的情况。保留了激子图像，并且从一开始就内置了刘维尔路径之间的大抵消。研究了光子回波和双量子相干技术对频率涨落、分子重取向、分子间耦合以及双激子相干的灵敏度。光子回波对频率涨落和分子重取向特别敏感，而双量子相干为分子间耦合和双激子相干提供了独特的探测手段。
