The potential energy curves for the low-lying excited states of CH2Cl and CH2Br have been computed using the complete active space self-consistent field (CASSCF) with the cc-pVTZ basis sets. The vertical excitation energies for the excited states were calculated using the multireference internally contracted configuration interaction (MRCI) method with the cc-pVTZ basis set for CH2Cl, and cc-pVTZ and ECP basis sets for CH2Br. For CH2Cl and CH2Br, all the excited states studied are found to be repulsive along the C-Cl and C-Br coordinate. (C) 2001 American Institute of Physics.