Carbon
Nanotube Stiffness

Brownian bending fluctuations of two nanotubes with different diameters seen by near-infrared intrinsic fluorescence microscopy of semiconducting
single-walled carbon nanotubes (SWCNT) in water. The (7,5) SWCNT has a smaller diameter than (9,8) SWCNT and hence the bending fluctuations are more pronounced.
Aggregation of SWCNTs into bundles strongly quenches the emission, so there is good discrimination against nanotube bundles.