WebMO Support Forum

I wish to keep atom numbers I have assigned, but WebMO Build re-orders the atoms. For example I have a hydroxide-4-water cluster, atoms1-14. If I add a CH3 to one O to make methanol, WebMO makes C #15 initially, but doing a SP calculation or opening the z-matrix tool, changes C to atomno = 1. My numbering after all has certain logic, i.e. all the contiguous H's and O's are number continuously.

WebMO preserves atom numbers UNTIL you add/delete an atom. This is because adding/deleting an atom forces regeneration of a the z-matrix. You should be able to re-order the atoms as you choose in the z-matrix editor (or possibly even the Cartesian editor).