Electronic Specific Heat of DNA: Effects of backbones and disorder

Sourav Kundu, S. N. Karmakar

Published 2014-12-03Version 1

In this present work we report the results of our investigation on the electronic specific heat of the DNA molecule within tight-binding framework by using the dangling backbone ladder model. We have studied both electronic specific heat and density of states in order to supplement our results. We take four different DNA sequences namely poly(dA)-poly(dT), poly(dG)-poly(dC), Random ATGC and a Fibonacci sequence, where the first two are periodic, third one is random and the last one is a quasi-periodic sequence (where A is adenine, T is thymine, G is guanine, and C is cytosine). The roles of backbone structure and the environmental effects on the electronic specific heat are discussed. We observe that irrespective of the sequences we have taken there is a universal response of the electronic specific heat for both the clean case and even in presence of environmental fluctuations. The nature of response of specific heat on backbone disorder is totally opposite in the low and high temperature regime.