Elasticity of single-crystalline graphite: Inelastic x-ray scattering study

Abstract

The five independent elastic moduli of single-crystalline graphite are determined using inelastic x-ray scattering. At room temperature the elastic moduli are, in units of GPa, ${C}_{11}=1109$, ${C}_{12}=139$, ${C}_{13}=0$, ${C}_{33}=38.7$, and ${C}_{44}=4.95$. Our experimental results are compared with predictions of ab initio calculations and previously reported incomplete and contradictory data sets. We obtain an upper limit of $1.1\phantom{\rule{0.3em}{0ex}}\mathrm{TPa}$ for the on-axis Young's modulus of homogeneous carbon nanotube, thus providing important constraints for further theoretical advances and quantitative input to model elasticity in graphite nanotubes.