The REMPI spectrum of molecular nitrogen, N-2, Was examined by tuning a focused ArF excimer laser beam in the range of 51600-51800 cm(-1) and collecting the fluorescence from the Hopfield lines (B-2 Sigma(+)(u)-X-2 Sigma g(+) of N-2(+)). The resulting spectrum was tentatively assigned at the two-photon level to rotational structure in the double a"(1) Sigma(+)(g)-(1)Sigma(+)(g) (II) potential energy well. To our knowledge this double well has not been seen experimentally before. (c) 2007 Elsevier B.V. All rights reserved.