Theoretical study on the interaction of neutral and charged Ti n ( n = 1–7) clusters with one oxygen molecule

The interactions between the neutral and charged (−2, −1, +1, and +2) Ti n ( n = 1–7) clusters and one O 2 molecule were investigated by density functional theory. The calculated results show that the oxygen molecule is dissociative on the neutral Ti n clusters. Geometrically, the two O atoms are distributed at the two sides across the neutral Ti n cluster for n = 1–4 and the oxygen atom favors the three‐fold hollow site for n = 5, 6, and 7. The binding energy per atom ( E b ) and energy gap ( E gap ) show higher stability and lower chemical activity of the neutral Ti n O 2 ( n = 1–7) systems compared with the corresponding Ti n clusters. The adsorption energies ( E ad ) exhibit a continuously ascending tendency except for n = 4. The results of the addition of different charges (−2, −1, +1, and +2) on the most stable neutral Ti n O 2 ( n = 1–7) systems indicate that their geometries are usually perturbed. The stabilities of the neutral Ti n O 2 systems are enhanced by adding one negative charge. The strongest interaction of the charged Ti n clusters (−2, −1, +1, and +2) with O 2 molecule is found at charge +2. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011