DFT study on the selective complexation of B<sub>12</sub>N<sub>12</sub> nanocage with alkali metal ions

<p>Quantum chemistry calculations indicate that BN nanocage is a good candidate for selective complex formation with Li<sup>+</sup> in the presence of different alkali metal ions.</p> <p>Density functional theory (DFT) calculations were applied at the M05-2X/6-311++G(d,p) level of the theory to investigate the interaction of the B<sub>12</sub>N<sub>12</sub> nanocage (BN) and alkali metal ions (Li<sup>+</sup>, Na<sup>+</sup>, K<sup>+</sup>, Rb<sup>+</sup> and Cs<sup>+</sup>) in the gas phase and in water. On the basis of the results, BN nanocage is able to form a selective complex with Li<sup>+</sup>. Water, as a solvent, reduces the stability of the metal ion-BN complexes in comparison with the gas phase. Natural bond orbital (NBO) and quantum theory of atoms in molecules (QTAIM) analyses, reveal that the electrostatic interaction between the BN and metal ions can be considered as the driving force for complex formation in which the role of water is of significance. Density of states (DOSs) analysis of the BN nanocage structure in the presence of different metal ions showed a noticeable change in the frontier orbitals, especially in the gas phase, and Fermi level shifting toward the lower values.</p>