vables</span><span class="o">.</span><span class="n">hartree_potential</span><span class="p">(</span><span class="n">s</span><span class="p">,</span> <span class="n">n</span><span class="p">)</span>
    <span class="n">E</span> <span class="o">-=</span> <span class="n">iDEA</span><span class="o">.</span><span class="n">observables</span><span class="o">.</span><span class="n">hartree_energy</span><span class="p">(</span><span class="n">s</span><span class="p">,</span> <span class="n">n</span><span class="p"