ESFF force field

Molecular modelling of 40 complexes derived from ten bicyclic phosphoranes (51-60), and the alkali cations, Li", Na" and has been carried out using the Insight II V97 programme based on the ESFF force field/ Calculations were... 

Figure 10.30 Space filling model of 10.29, the 12 Pt(II) containing cubeoctahedron calculated by ESFF (extended systematic force field) methods. (Reprinted with permission from Macmillan Publishers Ltd).

ESFF has been designed to be universal [187]. The Morse potential is employed for bond stretching, the potential quadratic in the cosine of the valence angles for their bending and the harmonic potential for the out of plane force field. The 6-9 with the charge based electrostatic potential is used for nonbonding interactions. No cross terms are involved. 

Shi, S., et al., An extensible and systematic force field, ESFF, for molecular modeling of organic, inorganic, and organometallic systems. J Comp Chem, 2003 24 1059. 

The Extendible Systematic Force Field (ESFF) [96] is a general force field for organic, organometallic, and transition metal compounds. The parameters used are based solely on data derived from first principles, from which all parameters needed for the force field are determined by a set of mles. The ESFF uses a systematic approach to atom types, based on hybridization, oxidation state, and coordination number, as well as flexible types attached to the atom which can vary depending on the chemical environment. 

A. M. Schneider and P. Behrens, Chem. Mater., 10,679 (1998). Molecular Mechanics Study on Organometallic Complexes in Crystalline Silica Matrixes Using the ESFF (Extensible Systematic Force Field). 

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