| Acronym | Meaning |
| TFDW | Thomas-Fermi-Dirac-Von Weizsaecker (method For Electronic Structure Calcns. On Mols.) |
| CNDO/FK | Complete Neglect Of Differential Overlap/ Fischer-Kollmar |
| BOA | Born-Oppenheimer Approxn. |
| PICI | Positive-ion Chemical Ionization |
| CLBO | Cesium Lithium Borate |
| MLSS | Mixed Liquor Suspended Solids |
| IEAES | Ion Excited Auger Electron Spectroscopy |
| FDMS | Field-desorption Mass Spectrometry |
| IIA | Information Industry Association |
| SV | Space Velocity |