  The magnetic susceptibility of a new one-dimensional, S=1 system, the
vanadium oxide LiVGe2O6, has been measured. Contrary to previous S=1 chains, it
exhibits an abrupt drop at 22 K typical of a spin-Peierls transition, and it is
consistent with a gapless spectrum above this temperature. We propose that this
behaviour is due to the presence of a significant biquadratic exchange
interaction, a suggestion supported by quantum chemistry calculations that take
into account the quasi-degeneracy of the t2g levels.
