I've been trying to track this down, but google is giving paywall papers that don't appear to be directly related to computational science, or simply don't explain the source algorithm.
There's an account on shadertoy that has been showing off this method, but does not know where it came from and got it from someone else on the site. These are some examples of this method in action:
as far as I can tell, it relies on closest particles to any given point in a cell, but somehow manages to avoid checking more than adjacent particles. I really don't understand what is going on beyond that.