Supplementary material

Nuclear coordinates for the optimized structures, basis set variation, Fourier coefficients of the potential curves and the 2D-PES, potential energy surface depending on the dihedral angles α1 and α2 calculated at the at the MP2/6-311++G(d,p) and B3LYP-D3BJ/6-311++G(d,p) levels of theory, and frequency list本数据集涵盖优化后结构的原子核坐标、基组变化相关数据、势能曲线的傅里叶系数，以及依赖于二面角α₁与α₂、在MP2/6-311++G(d,p)与B3LYP-D3BJ/6-311++G(d,p)理论水平下计算得到的二维势能面（2D-Potential Energy Surface，2D-PES），同时包含频率列表。