Executive Summary : | The researchers have developed state-of-the-art program packages to explore non-adiabatic effects in chemical physics. The "ADT" package will be used to construct diabatic potential energy surfaces (PESs) of aromatic molecules like pyridine, naphthalene, anthracene, and perovskite molecules. The OpenMP parallelized Time-Dependent Discrete Variable Representation (TDDVR) dynamics code, 'QuaS_Photo_Electron_Spectra', will solve multi-state multi-mode molecular Hamiltonian involving millions of differential equations for the simulation of photoelectron spectra of various molecules with large nuclear degrees of freedom. The researchers are studying reaction dynamics on multiple electronic states, which is a new challenge worldwide. They have developed an in-house code, 'TD_HYSP_ABC', which can perform reactive scattering calculations in hyperspherical coordinates on diabatic PESs with zero and non-zero total angular momentum cases. This will help compute various reaction attributes of triatomic scattering processes. The researchers have also made the quantum treatment of surface modes using Bose-Einstein statistics, revealing novel vibrational quantum effects and surface atoms' recoil effects on quantum dynamical outcomes with increasing surface temperature. They found the origin of surface temperature effects by incorporating linear coupling between molecules and surface modes and are introducing anharmonic quadratic coupling to reveal its contribution to thermal alteration of reaction/scattering outcomes. However, there is a shortage of high-performance computing facilities with high-end physical memory to complete these multi-dimensional complex calculations within a reasonable time frame. |