Geometries, frequencies, and energies of the 1(2)B(1), 1(2)A(2), 1(2)B(2), 2(2)B(1), 1(2)A(1), 2(2)B(2), and 3(2)B(1) states of C6H5Cl+ and potential energy curves (PECs) for Cl-loss dissociations in the 1(2)B(1), 1(2)A(2), 1(2)B(2), and 1(2)A(1) states were calculated by using the CASPT2//CASSCF methods in conjunction with an ANO basis. The CASPT2//ASSCF adiabatic excitation energies and CASPT2 relative energies for the seven states are in good agreement with experiment. The CASPT2//CASSCF PEC calculations predict the 1(2)A(1) state to correlate with C6H5+(1(3)B(1)) + Cl and show importance of using multiconfiguration-based methods. The B3LYP calculations were performed for 1(B1)(2), 1(2)A(2), 1(2)B(2,) and 1(2)A(1), but the PEC calculations for 1(2)A(2) were not successful. (c) 2005 Elsevier B.V. All rights reserved.