How to choose nrad / nang values for a molecule

[joshkamm]

Hey @ndmeier25! So @gosreya was asking me how we pick nrad / nang values for a molecule. I'm helping with infrastructure but haven't been a user so I'm not sure and and I'm not aware of us having documentation for SlaterGPU beyond installation instructions. I'm creating this issue thinking we might as well at least have a public record of already answered questions as some level of documentation. If you don't know we can tag Paul.

[ndmeier25]

As far as I'm aware, nrad and nang are selected to be a set Lebedev grid order. They are then converted to grid sizes, as shown in lines 137-144 in examples/main.cpp. I'm not entirely sure how the grid orders are selected, but I have been using the same order for all of my testing. @paulzim46 can correct me if I'm wrong.