\\ Species Tag:        &   52012 & Name:&  DNCCC  
\\ Version:            &       1 & & 
\\ Date:       &  Jan. 1995      & & 
\\ Contributor:&  M. L. Delitsky & &
\\             &  H. M. Pickett  & &
\\ Lines Listed:       &    3098 & Q(300.0)=&   12778.1637
\\ Freq. (GHz) $<$     & 861.502 & Q(225.0)=&    9591.6915
\\ Max. J:             &      99 & Q(150.0)=&    6395.7308
\\ LOGSTR0=            &   -10.0 & Q(75.00)=&    3199.2303
\\ LOGSTR1=            &  -100.0 & Q(37.50)=&    1601.0829
\\ Isotope Corr.:      &  -3.824 & Q(18.75)=&     802.0379
\\ Egy. (cm$^{-1}$) $>$&         & Q(9.375)=&     402.5269 
\\ $\mu_a$ = & 5.665             & A=&        
\\ $\mu_b$ = &                   & B=& 4400.593
\\ $\mu_c$ = &                   & C=&          
\headend

The observed laboratory frequency measurements were taken from Y.
Hirahara, Y. Oshima and Y. Endo, 1993, Astrophys. J. {\bf 403}, L83.

The dipole moment for HNCCC was calculated by P. Botschwina, M. Horn, S.
Seeger and J. Fl\"ugge, 1992, Chem. Phys. Lett. {\bf 195}, 427.  The
same value was assumed for DNCCC.

Although quantum calculations of the structure indicate that the
molecule may be non-linear, spectral measurements are available 
only for the $K=0$ state. For the purposes of fitting the spectra
and predicting frequencies and intensities, the $K=0$ states are 
equivalent to a linear molecule. The catalog entries for this 
species are currently presented as a linear molecule, and the 
intensities are calculated for a unit concentration of $K=0$ molecules
in the ground vibrational state.