Exploring electronic structure of a few biomolecules and graphitic materials

Abstract

Biomolecules are a class of soft-materials, which are considered to be essestial for controlling various physiological functions in all living organisms. Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA), the most relevant biomolecules, are the polymer of nucleotide, which contains nucleobases and sugar-phosphate backbone. In 1953, Watson and Crick [1] first proposed the DNA double helical structure, which describes the unique base-pairing effects in canonical duplex, DNA. Specific base sequences of duplex nucleic acids stores the genetic informations. Moreover, the nucleic acids also regulate and catalyze various important biological processes. In order to perform these diverse biological functions, nucleic acids, not only form the canonical duplex structures, but it also adopts various non-canonical conformations. In fact, there are various non-cannonical nucleic acid structures, which includes triplexes, hairpin loops, cruciform, poly(dA), duplex (A-motif) junctions, Gquadruplex structures, and many other higher order structures [2–5]. Among all these non-standard nucleic acids structures, G-quadruplexes have drawn much attention because of their both in vivo and in vitro applications. Many experimental as well as theoretical studies have been devoted to deeply understand their biological functions and possible nanobiotechnological applications [6–12].