Consistent valence force field CVFF

In a well-parametrized force field a large number of different situations are distinguished. In the Consistent Valence Force Field (CVFF) of Biosym Inc. [33] used in the present paper, 15 different types of carbon atoms (like aromatic, carboxylic, etc.) are provided to permit a realistic energy function for a great variety of compounds. Prior to using an empirical force field it... 

The geometries themselves are generated by a force field minimization with the widespread Consistent Valence Force Field (CVFF) (Sect. 2.3) of Biosym Inc. [33]. The dihedral angles are forced to their selected values t9/ by an additional potential... 

The consistent force field (CFF) was developed to yield consistent accuracy of results for conformations, vibrational spectra, strain energy, and vibrational enthalpy of proteins. There are several variations on this, such as the Ure-Bradley version (UBCFF), a valence version (CVFF), and Lynghy CFF. The quantum mechanically parameterized force field (QMFF) was parameterized from ah initio results. CFF93 is a rescaling of QMFF to reproduce experimental results. These force fields use five to six valence terms, one of which is an electrostatic term, and four to six cross terms. 

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