Spatial multistability and nonvariational effects

We investigate the phenomenon of spatial multistability of fronts in thin bistable systems and stress the important role played by the absence of a variational principle. Nonvariational effects allow, for instance, two different immobilized fronts to coexist. The morphological instability of the corresponding nucleating solution can then lead, even in the absence of any diffusive instability, to nontrivial patterns in the depth of one-side-fed reactors. [S1063-651X(99)50406-6].