\begin{table}%t3 
\caption{\label{tab3}Predicted rotational transition frequencies between the low-lying rotational levels of CH$_2$D$^+$ in the ground state (in MHz).}
\small%\centering
\par
\begin{tabular}{cr@{}lcr@{}l}
\hline\hline\noalign{\smallskip}
\multicolumn{3}{c}{$para$-CH$_2$D$^+$}&\multicolumn{3}{c}{$ortho$-CH$_2$D$^+$} \\
\multicolumn{1}{c}{Transition}& \multicolumn{2}{c}{Frequency\tablefootmark{a}} &\multicolumn{1}{c}{ Transition}&\multicolumn{2}{c}{Frequency\tablefootmark{a}} \\
\hline
   $1_{01}{-}0_{00}$  &     278~691.&656(26)    &  $2_{11}{-}1_{10}$  &    624~492.&647(21)    \\
   $2_{02}{-}1_{01}$  &     534~280.&362(153)   &  $2_{12}{-}1_{11}$  &    490~012.&249(31)    \\
   $3_{03}{-}2_{02}$  &     757~259.&34(30)     &  $3_{12}{-}2_{11}$  &    918~639.&68(25)     \\
   $4_{04}{-}3_{03}$  &     963~382.&45(25)     &  $3_{13}{-}2_{12}$  &    722~354.&621(26)    \\
   $5_{05}{-}4_{04}$  &     1~169~125.&70(66)    &  $4_{13}{-}3_{12}$  &    1~185~028.&50(69)    \\
                      &            &           &  $4_{14}{-}3_{13}$  &    945~398.&62(19)     \\        
   $3_{21}{-}2_{20}$  &     913~931.&77(46)     &  $5_{14}{-}4_{13}$  &    1~414~577.&97(116)   \\           
   $3_{22}{-}2_{21}$  &     835~464.&379(51)    &  $5_{15}{-}4_{14}$  &    1~161~990.&60(70)    \\      
   $4_{22}{-}3_{21}$  &     1~244~857.&02(71)    &                     &             &         \\
   $4_{23}{-}3_{22}$  &     1~095~330.&70(32)    &  $4_{31}{-}3_{30}$  &    1~176~104.&86(86)    \\
   $5_{23}{-}4_{22}$  &     1~556~427.&93(128)   &  $4_{32}{-}3_{31}$  &    1~147~307.&54(43)    \\  
   $5_{24}{-}4_{23}$  &     1~341~292.&62(76)    &                     &             &         \\       
                      &             &          &                     &             &         \\
   $2_{20}{-}2_{21}$  &      23~015.&873(169)   &  $1_{10}{-}1_{11}$  &    67~273.&548(45)     \\
   $3_{21}{-}3_{22}$  &     101~483.&26(62)     &  $2_{11}{-}2_{12}$  &    201~753.&947(70)    \\
   $4_{22}{-}4_{23}$  &     251~009.&58(129)    &  $3_{12}{-}3_{13}$  &    398~039.&01(23)     \\
                      &            &           &  $4_{13}{-}4_{14}$  &    637~668.&89(103)    \\
   $3_{22}{-}3_{03}$  &     666~882.&54(289)    &  $5_{14}{-}5_{15}$  &    890~256.&25(269)    \\
   $4_{23}{-}4_{04}$  &     798~830.&79(279)    &                     &           &           \\
\hline 
\end{tabular}
\tablefoot{\tablefoottext{a}{The values in parentheses indicate one standard deviation  to the last quoted digits.}  }\vspace{2mm}
\end{table}