Preserving the Integrity of Empirical Force Fields

Generalized force fields (FFs) act as extensions to biomolecular FFs to provide a wide coverage of organic molecules. However, their precise application to an arbitrary molecule presents a separate challenge. We show that MATCH assigns different atom types and bonded and nonbonded parameters than CGenFF, and the AM1-BCC charge model, commonly used with GAFF/GAFF2, does not exactly reproduce the performance of the RESP charge model. The results indicate the need for caution when employing FFs to ensure their integrity with respect to their implementation and validation.

Automated summary

Generalized force fields (FFs) are extensions of biomolecular FFs used for organic molecules. However, their application to arbitrary molecules requires caution to ensure their integrity.