Non-minimally coupled theories of special potentials are analyzed numerically . Such theories yield equations of state \omega < -1 and oscillations of the cosmological expansion , which are favored by the recent analysis of observations . Fitting these theories to the Gold SnIa dataset , we obtain results comparable with other models . A potential of the form V ( \phi ) = V _ { 0 } e ^ { a _ { 1 } \phi ^ { 2 } } yields \chi ^ { 2 } _ { min } = 170.127 . Similar results are obtained for potentials of the form V ( \phi ) = V _ { 0 } + a _ { 1 } \phi ^ { n } .