The electronic structure of the X²Σ⁺, A²Π, B²Σ⁺, 3²Σ⁺, and 2²Π state of LiCl^– anion are performed at an MRCI+Q level. Davison correction, core-valence correction and spin-orbit coupling effect are also considered. The ground state X²Σ⁺ of LiCl^– anion correlates with the lowest dissociation channel Li(²S_g) + Cl^–(¹S_g); the A²∏ state and B²Σ⁺ state correlate with the second dissociation channel Li(²P_u) + Cl^–(¹S_g); the 3²Σ⁺ state and 2²Π state correlate with the third dissociation channel Li^–(¹S_g) + Cl^–(²P_u).

Spectroscopic parameters are calculated by solving the radial Schröedinger equation. The equilibrium internuclear distance R_e of the ground state X²Σ⁺ is 2.1352 Å, which is a little bigger than the experimental datum, with an error being 0.5%. It is a deep potential well, and the dissociation energy D_e is 1.886 eV. These values are in good agreement with experimental data. The A²∏ state is at 13431.93 cm^–1 above the X²Σ⁺ state. The R_e is 2.1198 Å, which is only 0.0154 Å smaller than that of the X²Σ⁺ state. The values of energy level G_ν and rotational constant B_ν of five Λ-S states are also calculated. The values are in good agreement with available theoretical ones. The electronic structures of the excited states are also reported. The SOC effect weakly influences the spectroscopic parameters for the \textX^2\Sigma _1/2^ + , \textA^2\Pi _1/2 , \textA^2\Pi _3/2 , and \textB^2\Sigma _1/2^ + state. From the analysis of the SO matrix, it can be seen that the SOC effect plays a little role in realizing the A²Π \leftrightarrow X²Σ⁺ transition, so, it can be ignored.

The scheme of laser cooling of LiCl^– anion has constructed at a spin – free level. The A²∏(ν′) \leftrightarrow X²Σ⁺(v'' ) transition has a highly diagonally distributed Franck-Condon factor f₀₀ = 0.9898, the calculated branching ratio of the diagonal term R₀₀ is 0.9893, and spontaneous radiative lifetime of A²∏ is 35.45 ns. A main pump laser and two repumping lasers for driving the A²∏(ν′) \leftrightarrow X²Σ⁺(v'' ) transitions are required. The laser wavelengths are 744.10, 774.30 and 772.42 nm, respectively. Owing to the summation of R₀₀, R₀₁, and R₀₂ being closer to 1, the A²∏(ν′) \leftrightarrow X²Σ⁺(v'' ) transition is a quasicycling transition. These results imply that the LiCl^– anion is a candidate for laser cooling.