                       <span class="n">system_disturbed</span> <span class="o">=</span> <span class="n">system</span><span class="o">.</span><span class="n">copy</span><span class="p">()</span>
                        <span class="n">i_pos</span> <span class="o">=</span> <span class="n">system_disturbed</span><span class="o">.</span><span class="n">get_positions</span><span class="p">()</span>
                        <span class="n">i_pos</span><span class="p">[</span><span class="n">i_atom</span><span clas