MICRESS Forum

Dear Bernd:
According to my observation in experiment, nucleation is easier to happen in interface than bulk. And I want to simulate it with Micress. I know there are two nucleation models in Micress. One is seed undercooling model and another is seed density model. In my opinion, the formation energy of nuclies in interface is lower than that in bulk. When I use the seed undercooling model, there is no such step to enter formation energy. So should I use seed density model(but I also didn't find such a option to enter formation energy), or is there some other paramater to characterize the difficulty degree of nucleation in interface and bulk.
Best regards.
Dongxiao

Dear Dongxiao,

there is no option in MICRESS to directly enter a formation energy. Instead, we use a critical undercooling in the seed undercooling model. The way to provide different nucleation condition for bulk and interfaces would be to define two different seed types, one for bulk and one for interfaces, and provide them with different values of the critical undercooling.
The seed density model is a special model for heterogeneous nucleation from the melt and only applicable for nucleation in bulk or in a region. Here, the "formation energy" is provided as critical radius (=radius of seed particle), given in the density-radius distribution.

Bernd