row I ' ) } \ ,$"></TD>
<TD CLASS="eqno" WIDTH=10 ALIGN="RIGHT">
(<SPAN CLASS="arabic">5</SPAN>)</TD></TR>
</TABLE></DIV>
where the sign convention has been chosen to make M(Ek) real and symmetric under <!-- MATH
 $I \leftrightarrow I'$
 -->
<SPAN CLASS="MATH"><IMG
 STYLE=""
 SRC="img124.svg"
 ALT="$I \leftrightarrow I'$"></SPAN> interchange.
The diagonal reduced matrix element gives the spectroscopic quadrupole moment
<BR>
<DIV CLASS="displaymath">

<!-- MATH
 \begin{eqnarray}
Q_2 = \sqrt {{16 \pi} /5} ~ (