Chiang Mai Journal of Science

Properties of V₂O₅ clusters up to 1 nm size are investigated using density functional theory. The investigations include bond lengths, energy gaps, vibrational properties, formation energies, and heat capacities. Higher surface to the bulk ratio in clusters and nanomaterials affects many of their properties. Depending on the property, 1 nm cluster may have properties values ranging from less than half of that of bulk to twice the value of bulk. While bond lengths have approximately the same ranges, energy gaps are nearly twice their values in bulk. Raman longitudinal optical mode is blue-shifted with respect to bulk to higher frequencies. Gibbs free energy, enthalpy and entropy of formation and heat capacity have lower absolute values than bulk due to a larger number of surface dangling bonds and the absence of long-range interaction with other atoms. The absolute value of entropy of formation is exceptionally lower than half of that of bulk and can be used as an indicator for the nanocrystal size.