Study of oxide-based nano cluster X3O4 (X = Ti, Fe and Zn) for biomedical applications: a CDFT approach

In recent years, oxide-based nano clusters have shown some significant applications in medical sciences, bio sensing, catalysis, and energy storage. Here we have reported the computational study of oxide-based nano clusters X₃O₄ (X = Ti, Fe, Zn) by means of Conceptual Density Functional Theory (CDFT) method. Geometry optimization and frequency computation of these clusters are carried out using the functional B3LYP/LANL2DZ in the DFT framework. Highest Occupied Molecular Orbital (HOMO)–Lowest Unoccupied Molecular Orbital (LUMO) of the clusters are found between 2.019 and 3.570 eV. The global CDFT descriptors viz. hardness, softness, electronegativity, electrophiliicty index and dipole moment are calculated. Result shows that Zn₃O₄ has the maximum stability whereas Fe₃O₄ is highly reactive in nature. Electronegatiivty and electrophilicity index of these clusters decrease from Fe₃O₄ to Zn₃O₄ to Ti₃O₄. Analyses are conducted for the optical characteristics of X₃O₄ nano clusters, comprising their refractive index, dielectric constant, optical electronegativity and IR activity. Refractive index, dielectric constant and range of harmonic frequency increase from Zn₃O₄ to Fe₃O₄ via Ti₃O₄. The estimated bond length, HOMO–LUMO energy gap, refractive index and IR activity of the nano clusters are in agreement with the reported experimental and theoretical results. The physico-chemical properties of X₃O₄ nano clusters indicate their potential applications in biomedical sciences especialy for the treatment of cancer cells.