Raman Spectroscopic Study of the Effect of Strain Upon Carbon Nanotubes Marcel Lucas Materials Science Centre School of Materials U. of Manchester, UK Resonant Raman spectroscopy has proven to be a powerful and non-destructive tool to probe the structural, electronic properties of Single-Walled Carbon Nanotubes (SWNTs), and also the local strains in epoxy/SWNTs composites. The low-frequency Radial Breathing Modes (RBMs) are commonly used to characterize synthesis products, since their position is inversely proportional to the nanotube diameter. The RBM intensity variations in epoxy- and PVA-SWNTs composites were measured under uniaxial strain using three lasers of wavelengths 632, 780 and 830 nm. The results are consistent with resonance theory and the SWNT electronic band structure variations determined by tight-binding calculations. Using the RBM position and their electromechanical properties, a tentative chirality can be assigned to each RBM.