Automated reaction path searches for spin-forbidden reactions

作者：Takayanagi Toshiyuki^*; Nakatomi Taiki

来源：Journal of Computational Chemistry, 2018, 39(19): 1319-1326.

DOI：10.1002/jcc.25202

• spin-forbidden reaction
• transition metal
• reaction mechanism
• intersystem crossing
• potential energy surface

Many catalytic and biomolecular reactions containing transition metals involve changes in the electronic spin state. These processes are referred to as spin-forbidden reactions within nonrelativistic quantum mechanics framework. To understand detailed reaction mechanisms of spin-forbidden reactions, one must characterize reaction pathways on potential energy surfaces with different spin states and then identify crossing points. Here we propose a practical computational scheme, where only the lowest mixed-spin eigenstate obtained from the diagonalization of the spin-coupled Hamiltonian matrix is used in reaction path search calculations. We applied this method to the (FeO+)-Fe-6,4+H-2 Fe-6,4(+)+H2O, (FeO+)-Fe-6,4+ CH4 Fe-6,4(+)+CH3OH, and Mn-7(+)+OCS (MnS+)-Mn-5+CO reactions, for which crossings between the different spin states are known to play essential roles in the overall reaction kinetics.

• 出版日期2018-7-15