Quantum Rate Constants from Short-Time Dynamics: An Analytic Continuation Approach†
Quantum Rate Constants from Short-Time Dynamics: An Analytic Continuation Approach†
复制标题
短时动力学的量子速率常数：分析延拓方法†
DOI：
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
B. Berne
中科院分区：
文献类型：
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作者：
Eunji Sim;Goran Krilov;B. Berne
提出了一种利用短时通量自相关函数结合最大熵数值解析延拓格式计算多体系统中化学反应的量子正则速率常数的方法。速率常数表示为实时磁通自相关函数的时间积分。通过路径积分蒙特卡罗模拟，对实时通量自相关函数进行了短时间的全量子力学计算。然后利用最大熵法从短时间实时通量自相关数据中提取速率。我们提出了两个数值实验，一个是深隧道状态下谐波耗散环境下的质子转移，另一个是光合反应中心初级电荷分离的两能级模型。利用通量自相关数据得到的结果与精确量子计算的结果非常吻合，其时间不超过β ^ 2。
A method for calculating the quantum canonical rate constant of chemical reactions in a many body system by means of a short-time flux autocorrelation function combined with a maximum entropy numerical analytic continuation scheme is presented. The rate constant is expressed as the time integral of the real-time flux autocorrelation function. The real-time flux autocorrelation function is evaluated for short times fully quantum mechanically by path integral Monte Carlo simulations. The maximum entropy approach is then used to extract the rate from the short real-time flux autocorrelation data. We present two numerical tests, one for proton transfer in harmonic dissipative environments in the deep tunneling regime and the other for the two-level model of primary charge separation in the photosynthetic reaction center. The results obtained using the flux autocorrelation data up to the time of no more than βℏ are in excellent agreement with the exact quantum calculation over a wide range of parameters includ...