Journal of Physical Chemistry, Vol.98, No.36, 8831-8833, 1994
Ab-Initio Modeling of (LiF)(2) and (LiF)(2)(H2O)
Second-order Moller-Plesset perturbation theory (MP2) and correlation consistent basis sets have been employed to investigate energetics and minimum-energy structures for (LIF)(2) and its complex with one water, (LiF)(2)-(H2O). The computed dimerization energy for 2LiF --> (LiF)(2) of -61.8 kcal/mol [-59.9 kcal/mol with zero-point correction (ZPC)] compares very well with the experimental value of -59 kcal/mol. The cyclic C-1 minimum structure for (LiF)(2)(H2O) is very similar to that of LiF(H2O). The binding energy for (LiF)(2)(H2O) of -16.7 kcal/mol (-14.6 kcal/mol with ZPC) is nearly 20% smaller than the value of -20.3 kcal/mol (-17.9 kcal/mol with ZPC) for LiF(H2O). A transition state with C-2v symmetry is also discussed. A simple electrostatic argument indicates that this configuration will remain a transition state even with an extended substrate present.
Keywords:CORRELATED MOLECULAR CALCULATIONS;GAUSSIAN-BASIS SETS;WAVE-FUNCTIONS;SYSTEMATIC SEQUENCES;WATER