The energetics of inorganic nanotubes

The energetics of inorganic nanotubes (INTs) are investigated using both atomistic and continuum models. A relatively simple (Tersoff-II) potential model is used to study the energetics of carbon nanotube (C-NT) formation for use as a well-understood reference system. INTs formed by folding sections of MX stoichiometry constructed from both percolating hexagonal and square-net sheets are modelled. The C-NTs and hexagonal INTs are found to display folding energetics essentially consistent with a continuum elastic model. The square-net INTs are found to display folding energetics which are strongly dependent upon the direction along which the originating sheet is folded (and hence on the morphology of the formed INT). The difference in energies as a function of INT morphology is exemplified by reference to the high symmetry cases (the (n, 0)(sq) and (n, n)(sq) INTs) which are discussed in terms of the detailed atomistic interactions.