Molecular modelling of (eta(6)-arene)-Cr(CO)(3) complex systems: force field development of the monosubstituted complexes

In the present article we report our research on the (eta(6)-arene)-Cr(CO)( 3) rotational barrier and its preferred stable conformation. We propose a m olecular mechanics force field to describe the arene-Cr(CO)(3) rotation and the arene-metal bonding strength. The proposed torsional term is defined a s both the contribution of the arene-(CO)(3) non-bonded barriers and the ar ene-Cr electrostatic energy. In order to allow reliable validation of the c hosen model, we have first performed a vibrational calculation on the benze ne-Cr(CO)(3) and durene-Cr(CO)(3) complexes. Our molecular mechanics parame ters were implemented into the SYBYL force field. Comparison with other the oretical methods, SYBYL, MERCK force fields and PM3(tm) semi-empirical meth od in the SPARTAN package is also given. (C) 1999 Elsevier Science B.V. All rights reserved.