Highly Conducting Linear Chains of Sulfur inside Carbon Nanotubes

S1. Translational motion of 1D sulfur chains inside SWCNT Fig. S1 shows the observed translational motion of encapsulated sulfur chains during the HRTEM measurements. In the initial stage of the HRTEM observation, we find two lines inside the nanotube that extend across the entire SWCNT length (Fig. S1A). In subsequent observations taken several tens of seconds later (Fig. S1B), the length of the two lines has decreased. Owing to the fact that electron irradiation is unable to displace axially the entire inner wall of a DWCNT, we conclude that those two lines can be ascribed to the enclosed sulfur chains, not to the inner SWCNT. Since the two lines move simultaneously, we have reason to believe that the two 1D sulfur chains interact.