  We present a posteriori error estimates for a recently developed
atomistic/continuum coupling method, the Consistent Energy-Based QC Coupling
method. The error estimate of the deformation gradient combines a residual
estimate and an a posteriori stability analysis. The residual is decomposed
into the residual due to the approximation of the stored energy and that due to
the approximation of the external force, and are bounded in negative Sobolev
norms. In addition, the error estimate of the total energy using the error
estimate of the deformation gradient is also presented. Finally, numerical
experiments are provided to illustrate our analysis.
