All the Ways To Have Substituted Nanothreads

We
describe a general, symmetry-conditioned way of enumerating
isomers of saturated singly substituted one-dimensional nanothreads
of the (CH)5E and (CH)5CR type, where E is a
heteroatom and R is a substituent. Four nanothreads  so-called
tube (3,0), polytwistane, the zipper polymer, and polymer I, are treated
in detail. The methodology, combining symmetry arguments and computer-based
enumeration, is generally applicable to isomerism problems in polymers.