Vibrational energies for HFCO using a neural network sum of exponentials potential energy surface.
Vibrational energies for HFCO using a neural network sum of exponentials potential energy surface.
复制标题
使用指数势能面的神经网络总和计算 HFCO 的振动能。
DOI：
10.1063/1.4948440
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Alex Brown
中科院分区：
文献类型：
--
作者：
Ekadashi Pradhan;Alex Brown
采用神经网络指数拟合函数，对甲酰氟（HFCO）的六维势能面（PES）进行了乘积和形式的拟合。拟合所依据的从头算数据是在具有单、双和微扰三重激发的显式相关耦合簇[CCSD（T）-F12]/cc-pVTZ-F12理论水平上计算的。PES拟合在零点能量以上10 000 cm（-1）范围内是准确的（RMSE = 10 cm（-1）），并且覆盖了大多数实验测量的IR数据。PES是通过计算HFCO和氘代甲酰氟（DFCO）的振动能进行验证，使用块改进的松弛与多配置的时间相关的Hartree方法。的基本模式的频率，和所有其他振动状态高达5000厘米（-1）以上的零点能量，是更准确的比那些从以前的MP2为基础的PES。在PES上获得的振动频率与使用二阶振动微扰理论获得的MP2/aug-cc-pVTZ和CCSD（T）/aug-cc-pVTZ理论水平下的非谐频率进行比较。新的PES将有助于HFCO和DFCO的量子动力学模拟，例如，研究了导致单分子解离的分子内振动再分配及其激光控制。
A six-dimensional potential energy surface (PES) for formyl fluoride (HFCO) is fit in a sum-of-products form using neural network exponential fitting functions. The ab initio data upon which the fit is based were computed at the explicitly correlated coupled cluster with single, double, and perturbative triple excitations [CCSD(T)-F12]/cc-pVTZ-F12 level of theory. The PES fit is accurate (RMSE = 10 cm(-1)) up to 10 000 cm(-1) above the zero point energy and covers most of the experimentally measured IR data. The PES is validated by computing vibrational energies for both HFCO and deuterated formyl fluoride (DFCO) using block improved relaxation with the multi-configuration time dependent Hartree approach. The frequencies of the fundamental modes, and all other vibrational states up to 5000 cm(-1) above the zero-point energy, are more accurate than those obtained from the previous MP2-based PES. The vibrational frequencies obtained on the PES are compared to anharmonic frequencies at the MP2/aug-cc-pVTZ and CCSD(T)/aug-cc-pVTZ levels of theory obtained using second-order vibrational perturbation theory. The new PES will be useful for quantum dynamics simulations for both HFCO and DFCO, e.g., studies of intramolecular vibrational redistribution leading to unimolecular dissociation and its laser control.
影响因子：
1.7
作者：
H. Werner;G. Knizia;F. Manby
通讯作者：
H. Werner;G. Knizia;F. Manby