A new pair of singlet-triplet A(1)Sigma (-)(u) similar to b(3)Pi (u) mixed levels of (LiLi)-Li-6-Li-7 has been identified and used here as window levels in pulsed perturbation-facilitated optical-optical double resonance (PFOODR) experiments to study the high-lying triplet 2(3)Delta (g) state. The ne mixed le els reported here enhance access to the high-lying triplet states through the expansion of the Franck-Condon overlap factor range. at the same time allowing for more reliable determination of rotational constants, New molecular constants of the 2(3)Delta (g) state are reported here.