DFT Studies on Nucleic Acid Base (NAB)−M₂ /M₂ ²⁺ Complexes

Metal clusters, atomically precise aggregates of metal atoms, when prepared in the gas phase, produce only “magic numbers” sizes. Small-sized metal clusters (2 nm (<~100 atoms)) have different geometric and electronic properties as compared to bulk metal structures. Metal clusters are used as new functional nanomaterials in various applications. In this chapter, the interactive properties of different nucleic acid bases (NAB) with M2 /M2 2+ (M = Ag, Au, and Cu) are studied by theoretical means. Transition metals have a great affinity toward nucleic acids, which makes them suitable candidates for metal ion sensing, removal of toxic metal ions, and the construction of functional metal nanostructures. The highly significant symmetric dinuclear metalmediated homo base pairs structures with significant stabilities play a vital role in various applications. Metal-nucleobase complexes have wide applications, such as sensors, bidirectional nucleobases, logic gates, and nanowires. A logic gate programs cells for biomedical and environmental applications. In this chapter, the electronic and optoelectronic properties of M2 and M2 2+ with various NAB pairs, such as adenine−thymine (AT), adenine−uracil (AU), adenine thymine (ATAT) Watson Crick (WCST) stacking pairs, adenine−adenine stacking pairs (AAST), and adenine−adenine hydrogen bonding (AAHB) (M = Ag, Au, Cu), are studies, along with their applications.