The potential energy curves (PECs) of X¹Σ^+, a,³Σ^+, a³∏, A¹∏ states for GeO
molecule are calculated by themultireference configuration interactionmethod (MRCI)
and MRCI with the Davidson's corrections (MRCI+Q) with aug-cc-pVTZ basis set. All
these states involved dissociate into the same dissociation channel Ge(³P)+O(³P). For
the four states, the spectroscopic parameters (R_e, D_e, ω_e, B_e, ω_eχ_e and T_e) have been
obtained, which shows that our results are in very good agreement with the experimental
value and other theoretical data at MRCI+Q level. The dipole moments of
these states are also obtained. In addition, based on the accurate results of spectroscopic
constants atMRCI+Q level, the first 30 vibrational states are determined for the
four low-lying electronic states when J=0. The vibrational levels G(v) and inertial rotation
constants Bv at MRCI+Q level are calculated when J=0, the results of X¹Σ^+ and
A¹∏ states are in concordance with the available other theoretical values and experimental
work. The dissociation limits, dissociation energies, electronic configurations
at equilibriuminternuclear distance for a,³Σ^+, a³∏ states also are predicted for the first
time.