\documentclass[a4paper,12pt]{report}
\usepackage{german,pstricks}
\usepackage[latin1]{inputenc}
\begin{document}

% 12mm = 8 mm Breite + 2\tabcolsep
\psset{xunit=12mm, yunit=\baselineskip}
\tabcolsep=2mm
\pspolygon
  [fillcolor=lightgray,fillstyle=solid,linestyle=none]
  (0,-3.3)(0,2.7)(2,2.7)(2,1.7)(4,1.7)(4,0.7)(6,0.7)
  (6,-1.3)(7,-1.3)(7,-2.3)(5,-2.3)(5,-3.3)(4,-3.3)
  (4,-2.3)(3,-2.3)(3,-3.3)
\begin{tabular}{*{8}{p{8mm}}}
  H  &    &    &    &    &    &    & He\\
  Li & Be & B  & C  & N  & O  & F  & Ne\\
  Na & Mg & Al & Si & P  & S  & Cl & Ar\\
  K  & Ca & Ga & Ge & As & Se & Br & Kr\\
  Rb & Sr & In & Sn & Sb & Te & I  & Xe\\
  Cs & Ba & Tl & Pb & Bi & Po & At & Rn\\
  Fr & Ra & 112&    & 114&    &    &\\
\end{tabular}

\end{document}