What is the structure of the coordination complex with the formula Na2[AI(H2O)(ClO4)5]?

The coordination complex with the formula Na2[Al(H2O)(ClO4)5] has aluminum at the center due to its role as a central metal atom in the complex. Aluminum possesses a coordination number of six in many of its complexes, which corresponds to the presence of one aluminum ion coordinated to five perchlorate ions (ClO4-) and one water molecule (H2O).

In this specific complex, the aluminum ion serves as the Lewis acid, forming bonds with the surrounding ligands—five monodentate ClO4- ions and one water molecule. Each of these ligands donates a pair of electrons to form coordinate bonds with aluminum. This arrangement exemplifies a common characteristic of aluminum complexes, reflecting aluminum's ability to form stable coordination complexes.

Thus, the correct understanding of this coordination complex centers on aluminum being the central metal ion, highlighting its typical coordination chemistry and the nature of interaction with ligands. This is the foundation for why the choice pointing to aluminum at the center accurately represents the structure of the coordination complex.