Carbon nanothreads from polycyclic aromatic hydrocarbon molecules

Controlled Single-Crystalline Polymerization of C10H8·C10F8 under Pressure

“…One-dimensional, tube-like, linear, asymmetric, and symmetric chains can form, depending on the specific connectivity between neighboring molecules within the stacks, but all of these paths occur along the stacking axis. 36 The presence of layer lines in the experimental diffraction patterns (Figure 2 and Figure S4), which are commonly observed for one-dimensional fibers, 37 provides further confirmation of the 1D polymerization pathway. Figure 2 shows one polymerization pathway via a bond formation between topologically carbon atoms in naphthalene and octafluoronaphthalene.…”

“…Inferring that the polymerization proceeds via electrocyclic reactions, as in other cyclic aromatic systems, , there are multiple polymerization pathways possible along the stack axis (a model [4 + 2] cycloaddition pathway is shown in Figure S3). One-dimensional, tube-like, linear, asymmetric, and symmetric chains can form, depending on the specific connectivity between neighboring molecules within the stacks, but all of these paths occur along the stacking axis . The presence of layer lines in the experimental diffraction patterns (Figure and Figure S4), which are commonly observed for one-dimensional fibers, provides further confirmation of the 1D polymerization pathway.…”

“…Notably, the results here indicate the formation of the first nanothread structures formed from precursor molecules containing two aromatic rings. For pure naphthalene, these structures were calculated to exhibit exceptional 3D strength and elastic moduli . We note that the single-crystallinity observed here reflects the packing of these diamond-like rods within the monoclinic lattice, and we are therefore unable to solve the atomic crystal structure to obtain precise atomic positions.…”

“…For pure naphthalene, these structures were calculated to exhibit exceptional 3D strength and elastic moduli. 36 We note that the single-crystallinity observed here reflects the packing of these diamond-like rods within the monoclinic lattice, and we are therefore unable to solve the atomic crystal structure to obtain precise atomic positions. Unlike benzene nanothreads, 9 which exhibit clear pseudohexagonal packing, the nonhexagonal packing observed here is a result of the elliptical cross-sections of the C 10 H 8 and C 10 F 8 molecules.…”

Synthesis of double core chromophore-functionalized nanothreads by compressing azobenzene in a diamond anvil cell

“…19,20 Aer the discovery of nanothread formation from benzene, computational and experimental studies revealed the possibility of synthesising nanothreads from a large number of aromatics and heteroaromatics. Ab initio DFT calculations and classical MD simulations suggested the formation of fully saturated carbon nanothreads from polycyclic aromatic hydrocarbons 21 and from substituted benzenes (-CH 3 , -NH 2 , -OH, and -F). 22 The presence of such groups is extremely attracting in view of exploiting them for functionalization or for tuning the electronic properties without reducing the mechanical properties which are not substantially altered upon functionalization with respect to benzene derived nanothreads.…”