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How molecules are formed: generally two other molecules react. How molecules are formed: generally two other molecules react. What factors are involved?. Molecule R. Molecule S. Molecule R. Joined through atoms r and s. Molecule S. Molecule R. Joined through atoms r and s.
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How molecules are formed: generally two other molecules react
How molecules are formed: generally two other molecules react What factors are involved?
Molecule R Molecule S
Molecule R Joined through atoms r and s Molecule S
Molecule R Joined through atoms r and s Molecule S Makes a supermolecule
The possible interactions Molecule R Joined through atoms r and s Molecule S Makes a supermolecule
Molecule R Joined through atoms r and s Molecule S Lets look at FMO concepts L H Makes a supermolecule
Orbital Control Molecule R Joined through atoms r and s Molecule S Lets look at FMO concepts L H One gets preferential interaction between frontier orbitals closest in energy
Molecule R Joined through atoms r and s Molecule S Lets look at FMO concepts L H If there is substantial energy difference
Reactions are governed by charge control Molecule R Joined through atoms r and s Molecule S L H If there is substantial energy difference
Hard and Soft Acid Base Theory Charge control involves small, polarizable electron donors and acceptors
Hard and Soft Acid Base Theory Charge control involves small, polarizable electron donors and acceptors Large atoms with little or no charge almost unsovated and readily polarized
Relationship between hardness and electronegativity
Relationship between hardness and electronegativity Electronegativity = = (I + A)/2
Relationship between hardness and electronegativity Electronegativity = = (I + A)/2 Hardness = = (I-A)/2
Relationship between hardness and electronegativity I = E HOMO Electronegativity = = (I + A)/2 Hardness = = (I-A)/2 A = E LUMO
Relationship between hardness and electronegativity I = E HOMO Electronegativity = = (I + A)/2 Hardness = = (I-A)/2 A = E LUMO Thus, we see the useful relationship of hardness to FMO theory.
Thermochemical Data Bond energies (Homolytic) C-H 99 kcal/mol C-C 83 C-O 86 C-Cl 79 C-Br 66 C-I 52
Thermochemical Data Bond energies (Homolytic) C-H 99 kcal/mol C-C 83 C-O 86 C-Cl 79 C-Br 66 C-I 52
Thermochemical Data Bond energies C-H 99 kcal/mol C-C 83 C C 143 C C 194
Thermochemical Data Bond energies Try to know some trends: