Calculation Of Time-dependent Confined Space Self Consistent Field Of Some Small Molecular Systems

As a powerful tool to deal with multi-electron dynamics in strong laser fifield,multi-confifiguration time-dependent Hartree Fock（MCTDHF）method has attracted great attention.In this paper,the strategy of the implement of the MCTDHF theory is illustrated in the paper in detail.We develop three types of Fortran source soft packages based on three different bases to study correlated dynamics of atoms and molecules in strong laser field.The calculated soft-packages based on the theory are introduced in detail.The calculations are performed by using the soft-package.The prospect of the MCTDHF approach to simulating the multi-electron dynamics in strong laser field are also presented.In this paper,OH₂⁺/H₃ system without an external field was selected to study its reaction kinetics and Li H kinetics in the presence of an external field.The main research contents can be divided into three parts:1.The collisions（O,H₂⁺）are studied based on the ground state potential energy surface 12 A’’and the first excited potential energy surface 1²A’.Both two potential energy surface comprises deep well during the minimum energy reaction path.The average lifetime of the complex-formation of the title reactions as the function of translational energies are calculated.The results indicated that the average lifetime of the complex-formation decrease with the increasing of collision energy for both the two potential energy surfaces.There are two kinds of reaction mechanism,one is direct reaction mechanism;another is indirect reaction one.The indirect mechanism is dominated for all the collision energy studied.However,with the increasing of the collision energy,the direct reaction mechanism becomes more and more pronounced.Besides,the influence of the reagent excitation and the isotopic effect on the scalar properties and vector properties are studied in details respectively in this work.The reagent vibration excitation enhances the number of the direct reactive trajectories remarkably on 1²A’’,though it have nearly no influence on the average lifetime of the complex formation.In strong contrast,the reagent vibration excitation suppresses the number of the indirect reactive trajectories and reduces the average lifetime of the complex formation on the 1²A’.The isotopic variants have no influence on the scalar properties;however it affects the vector properties strongly2.We calculate the quantum dynamics of the initial ground state and the final first vibrational excited state of H+HBr reaction.The state resolution integral cross section of H+HBr reaction is given.The results show that the behavior of integral cross section is very different between HBr（v=0,j=0）and HBr（v=1,j=0）.The differential cross sections of H+HBr（v=1,j=0）reaction are also given.The results show that the trend of differential cross sections of H+HBr（v=0,j=0）reaction is significantly different from that of H+HBr（v=0,j=0）reaction.First,the lateral scattering of H+HBr（v=1,j=0）is more obvious than that of H+HBr（v=0,j=0）for low collision energies.Another difference is the variation in the strength of the differential cross section of backscattering at high impact energies.Finally,the dynamic distribution of H+HBr reaction vibration is given,and the mechanism of the trend of integral cross section and differential cross section is analyzed.3.Besides,we study the dynamics of Li H interacting with laser field,some interesting conclusions are available.The results show that the dipole moment varies with the magnetic field when E_max=0.03Au.When the field is larger,the dipole moment increases.When the pulse is off,the dipole moment disappears.Calculations of the charge distributions for the different orbitals show that the charge distributions for each orbit are zero when there is no field action.The charge distribution of the orbitals changes obviously when the orbitals are out of the field.The calculation of the time distribution of laser pulses shows that the initial energy of Li H is-185kcal/mol,and finally it becomes calm at about-180kcal/mol.After the addition of strong field,the energy of Li H increases by 5kcal/mol.The calculation of electron density shows that high power laser pulse can cause regular oscillation of electron density.The changes of charge distribution and nuclear spacing in the Ez and Exz directions of different orbitals indicate that a series of changes caused by laser irradiation are irreversible.The change of the effective charge number indicates that the Li and H charges have transferred.