The geometries of the reactants and product for the titled reaction are optimized at CAS(3,3)+1+2/cc-pvDZ level. The energetics of some crucial points along the minimum energy path are refined by CAS(3,3)+1+2/cc-pvTZ ...The geometries of the reactants and product for the titled reaction are optimized at CAS(3,3)+1+2/cc-pvDZ level. The energetics of some crucial points along the minimum energy path are refined by CAS(3,3)+1+2/cc-pvTZ method. Based on RRKM theory, the rate constants for the titled reaction are calculated with the geometries and frequencies of CAS(3,3)+1+2/cc-pvDZ. The obtained values are in good agreement with the experimental ones.展开更多
Iterative multireference configuration interaction (IMRCI) is proposed. It is exploited to compute the electronic energies of H2O and CH2(singlet and triplet states) at equilibrium and non-equilibrium geometries. The ...Iterative multireference configuration interaction (IMRCI) is proposed. It is exploited to compute the electronic energies of H2O and CH2(singlet and triplet states) at equilibrium and non-equilibrium geometries. The potential energy curves of H2O, CH2(singlet and triplet states) and N2 have also been calculated with IMRCI as well as the M?ller Plesset perturbation theory (MP2, MP3, and MP4), the coupled cluster method with single and double substitutions (CCSD), and CCSD with perturbative triples correction (CCSD(T)).These calculations demonstrate that IMRCI results are independent of the initial guess of configuration functions in the reference space and converge quickly to the results of the full configuration interaction. The IMRCI errors relative to the full configuration interaction results are at the order of magnitude of 10-5 hartree within just 2-4 iterations. Further,IMRCI provides an efficient way to find on the potential energy surface the leading electron configurations which, as correct reference states, will be very helpful for the single-reference and multireference theoretical models to obtain accurate results.展开更多
文摘The geometries of the reactants and product for the titled reaction are optimized at CAS(3,3)+1+2/cc-pvDZ level. The energetics of some crucial points along the minimum energy path are refined by CAS(3,3)+1+2/cc-pvTZ method. Based on RRKM theory, the rate constants for the titled reaction are calculated with the geometries and frequencies of CAS(3,3)+1+2/cc-pvDZ. The obtained values are in good agreement with the experimental ones.
基金supported by the National Natural Science Foundation of China(No.21473008 and No.21873011)
文摘Iterative multireference configuration interaction (IMRCI) is proposed. It is exploited to compute the electronic energies of H2O and CH2(singlet and triplet states) at equilibrium and non-equilibrium geometries. The potential energy curves of H2O, CH2(singlet and triplet states) and N2 have also been calculated with IMRCI as well as the M?ller Plesset perturbation theory (MP2, MP3, and MP4), the coupled cluster method with single and double substitutions (CCSD), and CCSD with perturbative triples correction (CCSD(T)).These calculations demonstrate that IMRCI results are independent of the initial guess of configuration functions in the reference space and converge quickly to the results of the full configuration interaction. The IMRCI errors relative to the full configuration interaction results are at the order of magnitude of 10-5 hartree within just 2-4 iterations. Further,IMRCI provides an efficient way to find on the potential energy surface the leading electron configurations which, as correct reference states, will be very helpful for the single-reference and multireference theoretical models to obtain accurate results.
