Properties of small TiO2, ZrO2 and HfO2nanoparticles

Abstract

Ground state structures and energies are predicted for (MO₂)_n, where n = 1 to 8 and M is one of three isovalent cations, titanium(IV), zirconium(IV) and hafnium(IV), with the minimised binding energies calculated using Density Functional Theory. An increased number of single coordinated oxygen atoms, as opposed to more densely packed configurations, were found for the titania ground state clusters n = 5 and 7. We present, as a function of n, calculated nucleation energies, the energies of the respective highest occupied and lowest unoccupied molecular orbitals, harmonic frequencies of vibration and infrared spectra for all three compounds. Similarities and differences in the data produced for the three oxides are considered. Calculations were performed using the GAMESS-UK software on HPCx (phase 2a); aspects of the computational procedures are discussed.