Overall, the findings from the present work articulate an idea about the complexation between the Ln(III) cation and imidazolium-PF6-based RTIL at the molecular level. However, the humidity of the RTIL is an important factor in controlling the liquid-liquid extraction and markedly depends on the exact water content in the RTIL . In the future, it would be interesting to study the solvation of RE cations in other "humid" imidazolium based RTILs with various anionic counterparts to understand their impact on the complexation phenomena from the computational aspect.