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\section{Introduction}
The study of the interaction of charged particles with matter has been a subject of extensive research over last few decades; it findings provide precise information for many technological applications such as nuclear safety, applied material science, medical physics and fusion and fission applications\cite{Komarov_2013}\cite{Patel_2003}\cite{Caporaso_2009}\cite{Odette_2005}. When a slow ion moves through a solid, it loses kinetic energy due to the excitations of the target electrons and the path of their trajectory. This phenomenon plays an important role in many experimental studies involving solids, surfaces and nanostructures. The complexity of describing the dynamic interaction between charged particles and solids has initiated a large amount of research both experimentally and and theoretically; in the latter the condensed matter community have initiated sophisticated computer simulation techniques with great success. Among the many measurable quantity the stopping power $\mathrm(S)$\cite{Ferrell_1977} has received much attention; it provided details information regarding the energy transfer between the incoming projectile and the solid target. The theoretical models employed to study stopping of elementary charged particles in solids\cite{Bloch_1933}\cite{Bethe_1930}, has stimulated this kind of study.
The velocity dependency of the stopping cross sections was reported earlier by Firsov {\em et al}\cite{Firsov} [6] and Lindhard {\em et al} \cite{Lindhard_1961}\cite{Sugiyama_1981} [7]. They have shown that there is a linear dependency of the electronic stopping power with the projectile velocity. In the low energy region for metal the energy loss is due to the excitation of a
small portion of electrons
near around the Fermi level to empty states in the conducting band. But at higher energies, a minimum momentum transfer of the projectile is possible due to its short duration near the target. In this region the electronic curve has a maximum due to the limited response time of target bound electrons to the projectile ions.
In recent times, the development of time-dependent methods have enhanced the diverse study of many body problems involving the slowing down of charged particles either in
matters matter or gases. The time dependent density functional theory (TDDFT) on the other hand has enjoyed much consideration owing to its electron dynamics both self-consistency and non-perturbative way.
Most recently Correa {\em et al}\cite{Correa_2012} have reported the role of radiation damage in ion-solid interactions. They have shown that the electronic excitations due to molecular dynamics are quite different from the adiabatic outcome. The inclusion of non adiabatic effects in real calculations remains a challenging problem even today. Schleife {\em et al}\cite{Schleife_2015} have calculated the electronic stopping by
H $\mathrm{H}$ and
He $\mathrm{He}$ projectile including non-adiabatic interactions employing first principles descriptions.
TIt It was observed that role of
both off-channeling trajectories
and consideration of semicore electrons enhances the
stopping power and the agreement with the experimental results.
Using a quantal method based on TDDFT, Quijada {\em et al}\cite{Quijada_2007} have studied the energy loss of protons and anti-protons moving inside metalic Al and obtained good results for the projectile-target energy transfer over a wider energy range.
Recently Uddin {\em et
al}\cite{Alfaz_Uddin_2013} al.}\cite{Alfaz_Uddin_2013} have calculated stopping cross sections for various media with atomic number
Z=2 $Z=2$ to
100 $100$ using realistic electron density with four fitted parameters and obtained close agreement (\sim 15\%) with the
SRIM \textsc{Srim} data.
However, their 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
represent represents accurately the electron dynamics\cite{Correa_2012}\cite{Schleife_2012}\cite{Schleife_2014} for proton impact collision of Cu surface.
We have tested the strength of this method to evaluate the electronic stopping
$\mathrm(S_e)$. $\mathrm(S_\text{e})$.
Our findings are compared with those
due to stopping and range of
ions in matter (SRIM) \textsc{Srim} as well as available experimental values.