MeCN molecules, with a Pd-N distance of 1.97 Å (Fig. ). This is in excellent agreement with the value obtained from the single crystal X-ray diffraction (SC-XRD) of the complex (Pd-N bond 1.96±0.01 Å). Two peaks around 3.3 Å, with a shoulder starting from 2.5 Å, and around 4.6 Å, are also observed. The latter peak is associated with the second solvation shell, with a coordination number of 8. The former peak corresponds to the interactions of acetonitrile molecules in the axial position, with a coordination number increasing from 4 to 6. The previous studies on Pd 2+ aqua complexes provided a foundation for understanding the axial interactions of Pd 2+ with MeCN. As mentioned the introduction, two paradigms exist in the literature. In the mesoshell paradigm, the two axial ligands are symmetrically bound, resulting in a sharp peak between the first and second solvation shells. Conversely, the "extended first solvation shell" concept suggests more weakly bound axial ligands, leading to a presence of broad peak. The structural features observed in the RDF in Fig. indicate that for Pd 2+ in acetonitrile, axial ligands interact according to the "extended first solvation shell" paradigm. This notion is further supported by the asymmetry in the average distance of the two axial MeCN ligands with respect to Pd 2+ (Fig. and).