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Molecular modeling and error sensitivity

Potential energy functions differ in what they can describe, and in what they can describe accurately. Proper choice of systems and error margins can reduce sensitivity to modeling errors in engineering applications. “All models are wrong, but some are useful.” [1]

Models and accuracy:

Link down  Quantum chemistry can describe motions, including changes in bonding

Link down  Standard molecular mechanics can describe only motions that leave bonding unchanged

Link down  Some potential energy functions accurately describe the geometries of important classes of structures

Questions and accuracy requirements:

Link down  Many molecular phenomena are sensitive to energy differences on the order of kT

Link down  Many molecular phenomena are insensitive to energy differences on the order of kT

Link down  The yields of reactions with large driving energies are insensitive to small variations in driving energy

Link down  Mechanically stiff mechanosynthetic systems can reliably block many unwanted reactions

Link down  The geometries of stiff molecular structures are relatively insensitive to details of the potential energy function

Link down  Experimental data can correct modeling errors

As cited by Stephen Duffull:

[1] Box, G.E.P. (1979) “Robustness in the strategy of scientific model building” In: Launer RL & Wilkinson GN Robustness in Statistics Academic Press pp. 202.

(cc) 2004 , revised: 12.05.2004

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