The geometric and electronic structures, energetics and spectroscopy of different complexes formed between cytosine and a molecule of [C_nmim]Br(n=2,4,6,8,10) are investigated in detail using the M06-2X and ωB97XD methods with 6-311++G(2d, p) basis set. A great number of stable C-[C₂mim]Br and C-[C₄mim]Br complexes were obtained, these structures are classified as three types: approximately coplanar, parallel and perpendicular. The BSSE-corrected binding energies of the most stable structures (C_n1) at the M06-2X method are -108.3 ∼ -97.3 kJ·mol^-1, which higher than the results of ɷB97XD. The aqueous solvation environment has an extremely weaken impact on the cytosine interaction with imidazolium bromide ionic liquid.

用M06-2X和ωB97XD方法详细研究了胞嘧啶与[C _n mim] Br（n = 2,4,6,8,10）分子之间形成的不同配合物的几何和电子结构，能谱和能谱。具有6-311 ++ G（2d，p）基础集。获得了大量稳定的C- [C ₂ mim] Br和C- [C ₄ mim] Br配合物，这些结构分为三种类型：近似共面，平行和垂直。在M06-2X方法中，最稳定的结构（C _n 1）的BSSE校正结合能为-108.3〜-97.3 kJ·mol ^-1，其结果高于ɷB97XD的结果。水性溶剂化环境对胞嘧啶与咪唑鎓溴化物离子液体的相互作用具有极弱的影响。