Portland State University. Environmental Sciences and Resources Ph. D. Program
Robert J. O'Brien
Date of Publication
Doctor of Philosophy (Ph.D.) in Environmental Sciences and Resources: Chemistry
Environmental Science and Management
Atmospheric Water vapor, Free radical reactions, Hydroxyl group
2, xiii, 116 leaves: ill. 28 cm.
Intermolecular complexes between Hâ‚‚O and atmospheric species HO, HOâ‚‚, Hâ‚‚Oâ‚‚, Oâ‚ƒ, NO and NOâ‚‚ have been studied by ab initio molecular orbital methods. The studies have been performed to the MP2 theory level by using 4-31G, 6-31G, D95, 6-31G**, D95**, 6-311G**, 6-311+G**, 6-311++G**, 6-311+G(2d,lp) and 6-311+G(2d,2p) basis sets. The geometries were fully optimized. The vibrational frequencies were calculated. The Basis Set Superposition Error (BSSE) were estimated. Finally, the binding energies of the complexes were predicted with other thermochemical properties. The binding energies of Hâ‚‚Oâ€¢HO, Hâ‚‚Oâ€¢HOâ‚‚, Hâ‚‚Oâ€¢Hâ‚‚Oâ‚‚, Hâ‚‚Oâ€¢Oâ‚ƒ, Hâ‚‚Oâ€¢NO and Hâ‚‚Oâ€¢NOâ‚‚ are estimated to be 5.7Â±0.6, 8.9Â±1.0, 7.3Â±1.3, 1.8Â±0.2, 1.17 (no BSSE correction) and 2.98 (no BSSE correction) Kcal/Mol, respectively. The Kcq for dimerization to yield Hâ‚‚Oâ€¢HO, Hâ‚‚Oâ€¢HF, Hâ‚‚Oâ€¢HOâ‚‚, Hâ‚‚Oâ€¢Hâ‚‚O and Hâ‚‚Oâ€¢Hâ‚‚Oâ‚‚ are estimated to be 0.11, 2.8, 3.3, 0.067 and 0.11 atmÂ¯Â¹, respectively. The Hâ‚‚Oâ€¢HO, Hâ‚‚Oâ€¢HF, Hâ‚‚Oâ€¢HOâ‚‚, Hâ‚‚Oâ€¢Hâ‚‚O and Hâ‚‚Oâ€¢Hâ‚‚Oâ‚‚ are quite strongly bonded complexes, while Hâ‚‚Oâ€¢Oâ‚ƒ, Hâ‚‚Oâ€¢NO and Hâ‚‚Oâ€¢NOâ‚‚ are only weakly bonded complexes. The Kcq changes with temperature are discussed, and their importance in atmospheric chemistry are addressed.
Pan, Xiong, "Theoretical Studies of Atmospheric Water Complexes" (1992). Dissertations and Theses. Paper 1163.