Are all three of those material objects? If we say that the first two are emergent properties of material things in a certain arrangement, there still seems a need for something relational, not something specifically bound to the material. In the same way that concrete numbers don't do much until you add operators - the times, pluses and so on.
There's a different quality between what something is, and what something does. The relational aspects, the interactions. Especially so when there is no apparent causal link and some state "just appears." In those cases, even a robust and detailed description doesn't capture what we want from a materialist outlook and we are left saying, "It just is that way."
I'm not saying there's a magical ingredient, just that a brick-and-mortar description doesn't satisfy unless we extend it by adding forces and so on. I think this is why light and photons have always fascinated scientists and philosophers. Light seems to be less about an "is" and more about a "does."