In the present work, through the path integral of Gaussian type correlation function, a new formalism based on Fermi-Golden Rule for calculating the rate constant of nonradiative decay process with Duschinsky rotation effect in polyatomic molecules is developed. The advantage of the present path-integral formalism is promoting-mode free. In order to get the rate constant, a "transition rate matrix" needs to be calculated. The rate constant calculated previously is only an approximation of diagonal elements of our "transition rate matrix " . The total rate should be the summation over all the matrix elements.
Recently, molecular electronics has become increasingly important. By applying the hybrid density functional theory coupled with the Green's function method, the current-voltage characteristics of the molecular junctions composed of gold-porphyrin-gold and gold-copper porphyrin-gold were investigated. The role of the metal coordination effect in organic molecular electron transport was highlighted. Although the thresholds of the bias voltage for both molecules were almost the same, approximately 0. 9 V, the metal compound showed a larger increase in current because of the metal-coordination-enhanced molecule-electrode coupling in the frontier molecular orbitals.
OUYANG Sheng-deYI Yuan-pingGENG HuaSHUAI Zhi-gangLUO Yi