arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2004.12404physics.chem-ph
收藏

N $_3^+$:全维势能面、振动能级和基态动力学

N$_3^+$: Full-Dimensional Potential Energy Surface, Vibrational Energy Levels and Ground State Dynamics

Debasish Koner, Max Schwilk, Sarbani Patra, Evan J. Bieske, Markus Meuwly

摘要:

在CCSD(T)-F_(12)和MRCI+Q水平上,通过三维势能面的量子束缚态计算,确定了N $_3^+$离子的电子基态的基本态和高振动激发态.在质量较高的CCSD(T)-F12表面上,振动基频位于1130 cm $^{-1}$($ν_1$,对称拉伸)、807 cm $^{-1}$($ν_3$,不对称拉伸)和406 cm $^{-1}$($ν_2$,弯曲)。对于$ν_1$,计算结果接近于实验(1170 cm $^{-1}$)和先前计算\cite{rosmus.n3:1994}(发现其在1190 cm $^{-1}$)的估计频率。在MRCI+Q PES上对振动态的计算与CCSD(T)-F12 PES上的计算定性一致。MRCI+Q计算的参考CASSCF波函数的分析提供了进一步的了解PES的形状,并支持Hartree-Fock作为耦合簇计算的参考波函数的可靠性。据此,N-$_3^+$在其电子基态($^3$ A-$''$)3d PES的所有低能区主要具有单参考特征.

英文摘要:

The fundamentals and higher vibrationally excited states for the N$_3^+$ ion in its electronic ground state have been determined from quantum bound state calculations on 3-dimensional potential energy surfaces (PESs) at the CCSD(T)-F12 and MRCI+Q levels of theory. The vibrational fundamentals are at 1130 cm$^{-1}$ ($ν_1$, symmetric stretch), 807 cm$^{-1}$ ($ν_3$, asymmetric stretch), and 406 cm$^{-1}$ ($ν_2$, bend) on the higher-quality CCSD(T)-F12 surface. For $ν_1$, the calculations are close to the estimated frequency from experiment (1170 cm$^{-1}$) and previous calculations\cite{rosmus.n3:1994} which find it at 1190 cm$^{-1}$. Calculations of the vibrational states on the MRCI+Q PES are in qualitative agreement with those using the CCSD(T)-F12 PES. Analysis of the reference CASSCF wave function for the MRCI+Q calculations provides further insight into the shape of the PES and lends support for the reliability of Hartree-Fock as the reference wave function for the coupled cluster calculations. According to this, N$_3^+$ has mainly single reference character in all low-energy regions of its electronic ground state ($^3$A$''$) 3d PES.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑