| Acronym | Meaning |
| VE-PPP | Variable Electronegativity PPP |
| AHF | Approximate Hartree-Fock Method |
| EIQ | Emission Inventory Questionnaire |
| OAPP | Oxidized Atactic Polypropylene |
| MCQR | Multiconfigurational Quadratic Response |
| BARF | Best Available Retrofit Facility |
| UCMR | Unregulated Contaminant Monitoring Regulation |
| GX | Generalized Exchange |
| LAXRD | Low-angle X-ray Diffraction |
| EPRI | Electric Power Research Institute |