Dialog Box: Growth Intervals [ Forms List Dialog] [ Forms List for Growth-Rate Constants Dialog]
In the discontinuous growth model, the total growth time is divided into intervals for each form, with a different constant growth rate for each interval. Zero is a possible growth rate. Two constants must be given for each interval, for each form; the Growth rate and the End time. The first interval starts at the start time for the crystal (which is zero for the main crystal, but may be less than zero for epitaxial crystals), and succeeding intervals start at the end of the previous interval. These times are absolute, although the main crystal always starts at time zero. Sixteen intervals are allowed for each form (but see the README file for the latest number).
Appearance and disappearance of forms in non-linear growth. In either the exponential or discontinuous models, forms may appear and disappear during growth. If the growth rate of a form is so large that it does not appear on a crystal after a given interval, its central distance is adjusted so that it lies just outside the current corners and edges. When the current growth rate for a form is sufficiently small relative to the other forms over a given growth interval, that form will appear, regardless of how large its rate may have been in previous growth intervals. Thus the central distance of a form is not the integral of the rate equation, if the form does not appear for any time.