The paper is organized as follows. The stage is set in Sec. 2, where the the differences between GEO and GEO are examined by using the HCN molecule as an example. In the same section, the set of accurate semiexperi-mental geometries is validated for the purpose of calculating GEO in the present work. The main results are in the next two sections, with Section 3 focusing on the quantification of geometric errors and trends across approximations, and Section 4 focusing on the GEO analysis (a breakdown of GEO into contributions from different geometric parameters). The last section is devoted to conclusions and discussion on where the GEO approach should prove powerful in the future.