Abstract Ab initio potential energy surface of Kr-NCCN complex has been investigated using the coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)], which including two mixed basis sets, aug-cc-pvDz for the C and N atoms, and aug-cc-pvDz-pp for the Kr atom, containing the midbond function of 3s3p2d1f1g. The potential energy surface of Kr-NCCN complex has a T-shaped global minimum locating at R = 6.96 a0, θ = 90° with the energy of −281.677 cm−1, the two equivalent local minima with the energy of −123.513 cm−1 locating at the linear geometry for R = 10.70 a0, and two saddle points between the global and the two local minima are located at R = 10.61 a0, θ = 10.1° and 169.9° with V = −123.304 cm−1, respectively. The bound state energies up to J = 9 for Kr-NCCN are calculated based on the potential energy surface by solving the Schrodinger equation, and the microwave transition frequencies are also investigated. Finally, the calculated spectroscopic constants are obtained based on the calculated rotational energy levels. These results could provide a theoretical basis for the experimental spectra research of Kr-NCCN complex.

中文翻译：

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Kr-NCCN配合物的从头算势能面和微波光谱

摘要 Kr-NCCN 复合物的从头算势能面已经使用耦合簇单重和双重进行了研究，其中非迭代包含连接的三元组 [CCSD(T)]，其中包括两个混合基组，Aug-cc-pvDz 用于 C和 N 原子，以及对于 Kr 原子的 aug-cc-pvDz-pp，包含 3s3p2d1f1g 的中键函数。Kr-NCCN复合物的势能面具有T形全局最小值，位于R = 6.96 a0，θ = 90°，能量为-281.677 cm-1，两个等效的局部最小值，能量为-123.513 cm- 1 位于 R = 10.70 a0 的线性几何，全局和两个局部最小值之间的两个鞍点分别位于 R = 10.61 a0、θ = 10.1° 和 169.9°，V = -123.304 cm-1。通过求解薛定谔方程，基于势能面计算 Kr-NCCN 高达 J = 9 的束缚态能量，并研究了微波跃迁频率。最后，基于计算的旋转能级获得计算的光谱常数。这些结果可为Kr-NCCN配合物的实验光谱研究提供理论依据。