Are isolated nucleic acid bases really planar? A Car-Parrinello molecular dynamics study

The ab initio molecular dynamics method along with the puckering analysis provides the new insight into the conformational phase space of nucleabases and pathways of their conformation transformations. The results have demonstrated that, despite the fact that planar geometry corresponds to a minimum on the PES, the geometries of the isolated DNA bases are distributed between many conformations in some space under ambient conditions.