Stabilization of hydrogen-bonded molecular chains by carbon nanotubes

Abstract

We study numerically nonlinear dynamics of several types of molecular systems composed of hydrogen-bonded chains placed inside carbon nanotubes with open edges. We demonstrate that carbon nanotubes provide a stabilization mechanism for quasi-one-dimensional molecular chains via the formation of their secondary structures. In particular, a polypeptide chain (Gly)N placed inside a carbon nanotube can form a stable helical chain (310-, α-, π-, and β-helix) with parallel chains of hydrogen-bonded peptide groups. A chain of hydrogen fluoride molecules ⋯FH⋯FH⋯FH can form a hydrogen-bonded zigzag chain. Remarkably, we demonstrate that for molecular complexes (Gly)N∈CNT and (FH)N∈CNT, the hydrogen-bonded chains will remain stable even at T=500 K. Thus, our results suggest that the use of carbon nanotubes with encapsulated hydrogen fluoride molecules may be important for the realization of high proton conductivity at high temperatures. Show more