Linear Carbon Chains under High-Pressure Conditions

Abstract

A high-pressure resonance Raman spectroscopy study of linear carbon chains encapsulated inside multiwalled carbon nanotubes (MWCNTs) is reported. While the frequencies of the tangential modes of carbon nanotubes (G band) harden as the pressure increases, the vibrational frequencies of the chain modes (around 1850 cm −1 ) decrease, thus indicating a softening of the carbon−carbon bonds in this 1D solid. Pressure-induced irreversible structural changes in the linear carbon chains are unveiled by the red shift in the vibrational modes when pressure is released. These results have been interpreted as being due to a coalescence of carbon chains, and this hypothesis is supported by state-of-the-art atomistic reactive molecular dynamics simulations.

Mechanical and energy-absorption properties of schwarzites

“…The inset shows one example of these reconstructions for the G8bal at 90% strain. LAC formation is a common feature in the simulations of fractured carbon-based materials, such as carbyne [62], novamene [63] and protomene [64], etc., and have been experimentally observed [65][66][67][68]. The structures of the P family presents a brittle behavior, which was also reported by Jung and Buehler [39] for similar structures.…”

On the mechanical properties of novamene: A fully atomistic molecular dynamics and DFT investigation

“…It is possible to observe that despite the brittle behavior, multiple linear carbon chains (LACs) are formed. LACs are common in fracture of carbon-based nanostructures and have been theoretically predicted and experimentally observed [33].…”

Materiais sob condições extremas

“…Isso acontece em particular na cristalização e modificação de algumas proteínas sob efeito de pressão aplicada (6). O uso de altas pressões também tem auxiliado na compreensão seletiva de nanotubos de carbono com parede dupla e tripla, principalmente pelo grupo de pesquisa na Universidade Federal do Ceará (7,8,9). Estudos de medicamentos (como betacaroteno, ácido acetilsalicílico, dentre outros) nas condições de altas pressões também têm sido desenvolvidos recentemente por vários grupos no Brasil.…”