how to change material properties of a mesh element in a loop

Hi

I am working with livelink to maltab and I have a geometry with three domains assigned with certain material properties. After solving my model for the first iteration, I take the results for each node or element and depenting on the values I get I need to change the material properties of that node or element.

I think that I can't use somehow the command
model.material('<mat tag>').selection.set([<point>]) e.g. for each point node, since the materials are assigned to domains, geometries or boundaries, right?

Do you have any idea about how to make it? For each iteration maybe I have to re-create the geometry including a new domain (even if this is an element) and then assign the domain with the new material properties? how can I create a new domain from matlab?

Thanks