Positive and negative parity bands in pear-shaped nuclei

The states of ground and K-pi = 0(-) bands are obtained though projection from an 'intrinsic' quadrupole and octupole-deformed ground state with non-definite reflection parity. An effective Hamiltonian and El transition operator are defined in terms of quadrupole and octupole bosons. Applications to (218,220,226),Ra show a very good agreement with available data. Finally the formalism is extended to another three pairs of positive-negative parity bands: (beta, 0(-)), (gamma, 2(-)), (1(+), 1(-)) The members of the last doublet are of magnetic and electric nature, respectively.