The neutron-rich nuclei 109 Nb and 110 Mo have been investigated by means of β-γ and isomer spectroscopy following in-flight fission of a 238 U beam at 345 MeV/nucleon at the RIBF facility. A T 1/2 = 150(30) ns isomer at 313 keV has been identified in 109 Nb. The low-lying levels in 109 Nb have been also populated following the β-decay of 109 Zr. The observed hindrances of the electromagnetic transitions deexciting the isomeric state are discussed in terms of possible shape coexistence. For 110

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... Mo, spectroscopic information on the low-lying levels of the quasi-γ band built on the 2 + 2 state at 494 keV has been obtained for the first time. The experimental finding of the 2 + 2 state being lower than the 4 + 1 level suggests that axially-asymmetric γ softness is substantially enhanced in this nucleus. The experimental results are compared with model calculations based on the general Bohr Hamiltonian method. A new project of decay spectroscopy at RIBF, named EURICA, is also introduced.