INITIAL GEOMETRIES

A first step is to determine initial reasonnable geometries that are going to be included in the GAMESS input file, before starting energy computation and geometry optimization. We have used the geometry database server CORINA (COoRdINAtes) that generates a set of atomic coordinates. In order to use CORINA one should enter the description of the molecule using a SMILES ( Simplified Molecular Input Line Entry Specification ) string. The SMILES strings concerning alkyl-oxonium cations under study are listed below.   SMILES string Name Formulae MethylOxonium Cation CH3-OH2+  C[OH2+] EthylOxonium Cation CH3-CH2-OH2+  CC[OH2+] 1-PropylOxonium Cation CH3-CH2-CH2-OH2+  CCC[OH2+] 2-PropylOxonium Cation CH3-CH(OH2+)-CH3  C(C)(C)[OH2+] 1-ButylOxonium Cation CH3-CH2-CH2-CH2-OH2 + CCCC[OH2+] 2-ButylOxonium Cation CH3-CH(OH2+)-CH2-CH3 CC(CC)[OH2+] IsoButylOxonium Cation (CH3)2-CH-CH2-OH2+  C(C)(C)C[OH2+] TertButylOxonium Cation (CH3)3-C-OH2+  C(C)(C)(C)[OH2+] MethylOxonioEthanol Cation CH3-(OH+)-CH2-CH2-OH  C[OH+]CCO MethylOxoEthylOxonium Cation CH3-O-CH2-CH2-OH2+ COCC[OH2+]

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