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We report the results of an {ab initio} calculation of vibronic (i.e. N=0) energy levels of the $CH+$2 molecular ion giving the lowest 19 levels of the ground $X¯2A1$ electronic state and the lowest 15 of the first excited $A¯2B1$ state. At the linear configuration these states become degencrate ($\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Pi$); the $X¯$ state is calculated to be bent at equilibrium with a barrier to linearity of $1089cm-1$, and the $(¯X)$ state is calculated to be linear at equilibrium. The potential energy surfaces were calculated over a wide range of nuclear geometrics using the multi-reference configuration interaction (MR-CI) level of theory with molecular orbital basis that were optimized separately for each state by complete-active-space SCF (CASSCF) calculations. The MOLCAS-1 programme system was used. The vibronic energies were calculated variationally using the Morse Oscillator Rigid Bender Internal Dynamics (MORBID) programme modified to include the effect of electronic angular momentum (the Renner effect). Results of $CD2+$ and $CHD+$ will also be reported, and it is hoped that we will be able to report preliminary results for $N>0$ levels.