Simultaneous evaluation of multiple rotationally excited states of H3(+), H3O(+), and CH5(+) using diffusion Monte Carlo.
Simultaneous evaluation of multiple rotationally excited states of H3(+), H3O(+), and CH5(+) using diffusion Monte Carlo.
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使用扩散蒙特卡罗同时评估 H3( )、H3O( ) 和 CH5( ) 的多个旋转激发态。
DOI：
10.1021/jp408821a
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
A. McCoy
中科院分区：
文献类型：
--
作者：
A. Petit;Jason E. Ford;A. McCoy
提出了一种扩展的扩散蒙特卡罗方法，用于同时计算流态分子的多个旋转激发态。该方法采用的旋转依赖性的波函数的对称顶部哈密顿的本征态方面的扩展。在该DMC方法内，每个步行者对于每个感兴趣的旋转状态具有单独的旋转状态向量。与每个步行者相关的旋转状态矢量的展开中的系数的值以及步行者的位置在基于虚时时间依赖性薛定谔方程的传播子的作用下在虚时中演化。首先将该方法应用于H3（+）、H2D（+）和H3O（+），可以将计算的能量与基准值进行比较。对于低至中等J值，发现DMC结果准确度在评价的统计不确定度范围内。的波函数的振动部分的旋转依赖性也进行了研究，并观察到显着的旋转振动相互作用。在此方法成功应用于H3（+）、H2 D（+）和H3 O（+）的基础上，将该方法应用于CH 5（+）（v = 0且J ≤ 10）的转动能和波函数的计算。基于这些计算，旋转能量的进展被证明是一致的，为一个接近球形的顶部分子，和很少的证据，发现在振动波函数的旋转振动相互作用。
An extension to diffusion Monte Carlo (DMC) is proposed for simultaneous evaluation of multiple rotationally excited states of fluxional molecules. The method employs an expansion of the rotational dependence of the wave function in terms of the eigenstates of the symmetric top Hamiltonian. Within this DMC approach, each walker has a separate rotational state vector for each rotational state of interest. The values of the coefficients in the expansion of the rotational state vector associated with each walker, as well as the locations of the walkers, evolve in imaginary time under the action of a propagator based on the imaginary-time time-dependent Schrödinger equation. The approach is first applied to H3(+), H2D(+), and H3O(+) for which the calculated energies can be compared to benchmark values. For low to moderate values of J the DMC results are found to be accurate to within the evaluated statistical uncertainty. The rotational dependence of the vibrational part of the wave function is also investigated, and significant rotation–vibration interaction is observed. Based on the successful application of this approach to H3(+), H2D(+), and H3O(+), the method was applied to calculations of the rotational energies and wave functions for CH5(+) with v = 0 and J ≤ 10. Based on these calculations, the rotational energy progression is shown to be consistent with that for a nearly spherical top molecule, and little evidence of rotation–vibration interaction is found in the vibrational wave function.
量子诱导对称性破缺解释了 CH(5)( ) 同位素异体的红外光谱
影响因子：
21.8
作者：
S. D. Ivanov;O. Asvany;A. Witt;E. Hugo;G. Mathias;B. Redlich;D. Marx;S. Schlemmer
通讯作者：
S. Schlemmer