Material & Symbol &$E_{\textup{g}}$ (\si{\electronvolt}) & Type \\
\midrule
\rowfont\bfseries
\multicolumn{4}{c}{Elements}\\
diamond &$C$& 5.46 & i \\
silicon &$Si$& 1.12 & i \\
germanium &$Ge$& 0.67 & i \\
selenium &$Se$& 1.74 & d \\
\midrule
\rowfont\bfseries
\multicolumn{4}{c}{IV-IV Compounds}\\
silicon carbide &$SiC 3C$&\num{2.36}& i \\
silicon carbide &$SiC 4H$&\num{3.28}& i \\
silicon carbide &$SiC 6H$&\num{3.03}& i \\
\midrule
\rowfont\bfseries
\multicolumn{4}{c}{III-V Compounds}\\
indium phosphide &$InP$&\num{1.27}& d \\
indium arsenide &$InAs$&\num{0.355}& d \\
gallium nitride &$GaN$&\num{3.37}& d \\
gallium arsenide &$GaAs$&\num{1.42}& d \\
aluminium nitride &$AlN$&\num{6.2}& d \\
\bottomrule
\end{tabu}
\caption{The bandgab of some semiconductors.}
\label{tab:table1}
\end{table}
\end{frame}
\begin{frame}{Demonstration}{Tables}
\begin{table}
% \tabulinesep=0mm
% \extrarowsep=0mm
% \extratabsurround=0mm
\setlength{\leftmargini}{4mm}
\centering
\resizebox{0.95\linewidth}{!}{%
\begin{tabu} to 2.5\linewidth{X[0.2,m]X[0.25,m]X[0.35,m]X[0.3,m]X[c,m]}\toprule
% \everyrow{\midrule}
\rowfont{\large\bfseries}
Unit name & Unit Symbol & Dimension symbol & Quanitity name & Definition\textsuperscript{\normalfont 1}
\\\midrule
\rowfont{\Large}
\textbf{metre}&\si{\m}& L & length &
\begin{itemize}\footnotesize
\item\textbf{Prior} (\num{1793}): \SI{1/10000000}{} of the meridian through Paris between the North Pole and the Equator.\textsuperscript{FG}
\item\textbf{Interim} (\num{1960}): \SI{1650763.73}{} wavelengths in a vacuum of the radiation corresponding to the transition
between the $\num{2}\textmd{p}^{\num{10}}$ and $\num{5}\textmd{d}^{\num{5}}$ quantum levels of the krypton-\num{86} atom.
\item\textbf{Current} (\num{1983}): The distance travelled by light in vacuum in \SI{1/299792458}{\second}.
\end{itemize}
\\\midrule
\rowfont{\Large}
\textbf{kilogram}\textsuperscript{\normalfont 2}&\si{\kg}& M & mass &
\begin{itemize}\footnotesize
\item\textbf{Prior} (\num{1793}): The grave was defined as being the mass (then called weight) of one litre of pure water at its freezing point.\textsuperscript{FG}
\item\textbf{Current} (\num{1889}): The mass of a small squat cylinder of $\sim$\SI{47}{\cubic\cm} of platinum-iridium alloy kept in the Pavillon de Breteuil, France.
Also, in practice, any of numerous official replicas of it.
\item\textbf{Future} (\num{2019}): The \si{\kg} is defined by taking the Planck constant h as exactly
\SI{6.62607015e-34}{\joule\second} (\si{\joule} = \si{\kg\square\meter\per\square\second}), given the definitions of the \si{\meter} and the \si{\second}.
\end{itemize}
\\\midrule
\rowfont{\Large}
\textbf{second}&\si{\second}& T & time &
\begin{itemize}\footnotesize
\item\textbf{Prior}: \SI{1/86400}{} of a day of \SI{24}{\hour} of \SI{60}{\minute} of \SI{60}{\second}.
\item\textbf{Interim} (\num{1956}): \SI{1/31556925.9747}{} of the tropical year for \num{1900} January \num{0} at \SI{12}{\hour} ephemeris time.
\item\textbf{Current} (\num{1967}): The duration of \num{9192631770} periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-\num{133} atom.
\end{itemize}
\\\midrule
\multicolumn{5}{l}{\textsuperscript{1} Interim definitions are given here only when there has been a significant difference in the definition.}\\
\multicolumn{5}{l}{\textsuperscript{2} Despite the prefix ``kilo-'', the kilogram is the base unit of mass.}\\
