#### sph2020

##### Newbie

I am looking for some new vocabulary. To be more specific I am looking at unitcells of a 3d perodic lattice that are filled with material to with various fill-fractions. For example please see the attached picture of a 3d simple cubic structure. In the first depicted unicell, it is completely filled with material. In the second depiction of the unitcell, you see that at the edges, holes start to appear. However, the holes are not connected yet, in contrast to the third depiction of the unitcell, where the holes are connected throughout the lattice. In the fourth example so much material has been removed from the unit cell that the material is not connected to its neighbouring unitcells.

Is there some mathematical property and language that describes this "connectedness" of a periodic medium?

Cheers,

sph