The Study Of Molecular Structures Properties, Analytic Potential Energy Function And Thermodynamic Properties For Pd-Y-H System

In this paper, the molecular structures, dissociation limits, spectroscopic data, thermodynamic data and potential energy functions have been presented based on the general principle of Atomic and Molecular Reaction Statics(AMRS), molecular structural theory, many-body expansion method for potential energy function and the approximate method for thermodynamic.The correct electronic states PdH(X²âˆ‘⁺),YH(X¹âˆ‘⁺),YH₂( X²A₁),YH₃( X¹A₁), Pd₂Y (X²B₂),PdYH(X²A'),Pd₂YH(X¹A₁) have been derived based on the Atomic and Molecular Reaction Statics , the reasonable dissociative limits have also been acquired.With the DFT method and the relativistic effective core potential(RECP) for Pd,Y atom and full electronic basis 6-311++g** for H atom ,the present work has optimized the equilibrium geometry for the ground states of the abovementioned molecules, whose equilibrium nuclear distance and dissociation energy have been derived. For the ground states of PdH,YH and PdY, the Murrell-Sorbie potential energy function have been derived to be fitted to ab initio data through the least square fittings, the spectroscopic data ,force constants and vibration frequency are also be acquired based on this.The analytic potential energy functions for the ground states of PdYH molecule have been derived by many-body expansion method using their equilibriumgeometry structure parameters, dissociation energy and harmonic force constants, these potential energy functions can be regarded as foundation for molecular reaction dynamic processes investigation.Considering the characteristics of different motion types, the vibrational energy or electronic and vibration entropy of the molecules are assumed to be the corresponding values of their solid states, the thermodynamic function AH9,AS'\AG