State-to-State\nTime-Dependent Quantum Dynamics Studies\nof the Si(<sup>3</sup>P) + OH(X <sup>2</sup>Π) → OSi(X <sup>1</sup>Σ<sub>g</sub><sup>+</sup>) + H(<sup>2</sup>S) Reaction

Quantum and quasi-classical dynamics\ncalculations were conducted\nfor the reaction of Si with OH on the latest potential energy surface\n(PES), which is obtained by fitting tens of thousands of <i>ab\ninitio</i> energy points by using the many-body expansion formula.\nTo obtain an accurate PES, all energy points calculated with aug-cc-pVQZ\nand aug-cc-pV5Z basis sets were extrapolated to the complete basis\nset limit. The accuracy of our new PES was verified by comparing the\ntopographic characteristics and contour maps of potential energy with\nother works. In addition, the anharmonic vibrational frequencies of\nHOSi and HSiO based on the present <i>ab initio</i> and\nPES by means of quantum dynamics methods were calculated. Dynamics\ninformation such as reaction probability, integral cross sections\n(ICS), product distribution, and rate constants was obtained on the\nnew HOSi(X<sup>2</sup>A′) PES. The dynamic information calculated\nusing the quasi-classical trajectory method and time-dependent wave\npacket method is generally in good agreement, except for the vibrational\nstate-resolved ICSs of product. The calculated differential cross\nsection and capture time reveal that the reaction is primarily governed\nby the complex formation mechanism.