An analytical sixhyphen;dimensional potential energy surface for (HF)2fromabinitiocalculations

摘要

We have developed an analytical expression for the 6D potential energy surface of (HF)2and fitted it to 1061abinitiopoints covering an energy range of up to 25thinsp;000 cmminus;1above equilibrium. Theabinitiocalculation used the coupled pair functional approach with an extended polarized basis set. We have adjusted 42 parameters (and constrained 7 others) in the fitting of the analytical function to the points; the standard deviation of the weighted fitting is 26.8 cmminus;1. The minimum energy path from the linear saddle point (345 cmminus;1above equilibrium), through the equilibrium point, to theC2hsaddle point (332 cmminus;1above equilibrium) has been determined, and several cuts through the potential are presented. We plan to use this potential surface in reaction path and close coupling calculations of rotationndash;vibration term values.