This monograph is based on the research done at Department of Physics, DDU Gorakhpur University Gorakhpur,India on unusual DNA structures.Department s laboratory is pioneer in the field of Computational Modeling, Quantum mechanics and Molecular Mechanics simulations (QM/MM) on bio-molecules. Several high end research articles and theses have been produced during last 10 years form the laboratory. The aim of writing this book is to provide an easy tool/manual to understand nucleic acids, its modeling, QM/MM simulations, conformation and biological functions to the graduate level students and...