The structure and dynamics of the chains of hydrogen bonds of hydrogen fluoride molecules inside carbon nanotubes

It is shown by molecular dynamics that hydrogen fluoride molecules inside single-wall carbon nanotubes with a diameter $D<$ 0.85 nm form flat zigzag chains of F–H $\cdots$ F–H $\cdots$ F–H$\cdots$ hydrogen bonds. The chains that are the closest to the chain of hydrogen bonds of OH hydroxyl groups in structure form hydrogen fluoride molecules inside nanotubes with the chirality indices (6, 6) and (10, 0). In such open nanotubes with narrowed down ends, the chains of (FH)$_N$ hydrogen bonds may fully fill in their internal cavity, thus forming a structure resistant to thermal vibrations in a wide range of temperatures. Stationary orientational defects localized on three to four chain units which divide the parts of the chain with the opposite orientations of the FH molecules can exist in the chains. (FH)$_N$ $\in$ CNT (6, 6) and (FH)$_{N}$ $\in$ CNT (10, 0) molecular complexes can act as proton-conducting “nanowires”, in which the external nanotube acts as the winding (insulation) which protects and stabilizes the internal proton-conducting chain of (FH)$_N$.