Confinement effects in dendritic growth

We study the interplay between crystal orientation and confinement in diffu sion-limited growth. Growth of the overall morphology in the direction of m inimal surface stiffness has been investigated in some detail by various au thors, the most recent advances being summarized by Brener et al (Brener E, Muller-Krumbhaar H and Temkin D 1996 Phys. Rev. E 54 2714). Here, we consi der competing influences, each trying to impose a different growth directio n. The simplest possible situation giving rise to such a competition is gro wth in a channel with a mismatch between the orientation of the channel wal ls and surface tension anisotropy. Analysing this situation, we find a new structure and gain further insight into the problem of morphological stabil ity. Another case is that of periodic boundary conditions, where the same a ngle of misorientation can be used to describe growth of a tilted array of finger-shaped crystals. It is found that the transition between dendritic a nd doublonic structures is affected by the rift.