Herman-Kluk propagator is free from zero-point energy leakage
Herman-Kluk propagator is free from zero-point energy leakage
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DOI：
10.1016/j.chemphys.2018.06.008
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发表时间：
2018-11-14
期刊：
影响因子：
2.3
通讯作者：
Ivanov, Sergei D.
中科院分区：
文献类型：
--
作者：
Buchholz, Max;Fallacara, Erika;Ivanov, Sergei D.
准经典技术构成了一个有前途的路线，以近似量子动力学的基础上，从量子力学正确的分布开始的经典轨迹。它们的主要缺点之一是所谓的零点能量（ZPE）泄漏，即由于经典的均分，能量从具有高频率和因此高ZPE的模式到具有低频率和ZPE的那些模式的人工重新分布。在这里，我们表明，精心设计的半经典形式主义的基础上的赫尔曼-克鲁克传播是免费的ZPE泄漏，尽管利用纯经典的传播。我们证明了这一点与二维和三维非谐耦合振荡器的应用程序的例子。这一发现开辟了道路，以正确的动力学模拟的系统与众多的自由度，不能完全量子力学处理，由于指数增加的数值努力。
Quasiclassical techniques constitute a promising route to approximate quantum dynamics based on classical trajectories starting from a quantum-mechanically correct distribution. One of their main drawbacks is the so-called zero-point energy (ZPE) leakage, that is artificial redistribution of energy from the modes with high frequency and thus high ZPE to those with low frequency and ZPE due to classical equipartition. Here, we show that the elaborate semiclassical formalism based on the Herman-Kluk propagator is free from the ZPE leakage despite utilizing purely classical propagation. We demonstrate this with example applications for two- and three-dimensional anharmonically coupled oscillators. This finding opens the road to correct dynamical simulations of systems with a multitude of degrees of freedom that cannot be treated fully quantum-mechanically due to the exponential increase of the numerical effort.