deletions | additions       diff --git a/section_Introduction_The_study_of__.tex b/section_Introduction_The_study_of__.tex  index d86d0c5..7db5983 100644  --- a/section_Introduction_The_study_of__.tex  +++ b/section_Introduction_The_study_of__.tex 
...
Recently Uddin {\em et al.}\cite{Alfaz_Uddin_2013} have calculated stopping cross sections for various media with atomic number $Z=2$ to $100$ using realistic electron density with four fitted parameters and obtained close agreement (\sim 15\%) with the \textsc{Srim} data.   Their parametrized model, explains the projectile energy loss in various stopping media reasonably well.   We report here an application of the TDDFT that embodies a plane-wave basis set that represents accurately the electron dynamics\cite{Correa_2012}\cite{Schleife_2012}\cite{Schleife_2014} for proton impact collision of Cu $\mathrm{Cu}$  surface. We have tested the strength of this method to evaluate the electronic stopping $\mathrm(S_\text{e})$.   Our findings are compared with those of \textsc{Srim} as well as available experimental values.