Effect of high pressure on diameter variation of carbon nanotube

The samples of C60@single-walled nanotube (SWNT) with the structures of both dimer and one-chain polymer was fabricated by high pressure using a diamond anvil cell (DAC). The samples with two polymerized structures were heated under Ar ambient, and it was found to be reversible, and deploy merized at high temperature. The samples of C60@SWNT with different diameters show different regularities during in polymerization and de-polymerization process. Smaller diameter of C60@SWNT is reversible in phaser transition, while larger diameter of C60@SWNT is not reversible. The regularities provide theoretical instruction to further study the physical properties of peapod samples, and provide an effective way to adjust the diameter of SWNT.