  We present microscopic wave functions of spin singlet Mott insulating states
and nematic Mott insulating states. We also investigate quantum phase
transitions between the spin singlet Mott phase and the nematic Mott phase in
both large-N limit and small-N limit (N being the number of particles per site)
in high dimensional bipartite lattices. In the mean field approximation
employed in this article we find that phase transitions are generally weakly
first order.

Condensed Matter