Parameterization, Approximations and Limitations of Molecular Mechanics

The energies resulting from these forces are related to the positions of the nuclei in a molecule, and therefore enforce the entire molecular structure. The energy lost by moving atoms away from their ideal positions is related to the strain or steric energy, L/totai [Eq. (3.1)] as a function of the nuclear geometry. 

Minimization of the strain energy 1/totai by rearrangement of the nuclei leads to an optimized structure and a value for the minimized strain energy. 

Similar effects are observed in coordination compounds. In Table 3.2, calculated and experimentally determined Co—N distances for various cobalt(III) hexaamines. 

1) MOMEC 97 [89] required Hyperchem for molecule display and building. MOMEC 3 [90] is a molecular mechanics program whidi was designed especially for coordination and inor- 

These points will be discussed further in Sections 3.3 and 3.5. 

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