Automatized Parameterization of DFTB for H2, O2, H2O, and H2O2

• Main Authors: Fan, Chin-Chai, 范錦財
• Other Authors: Witek, Henryk
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/xpz28t

碩士 === 國立交通大學 === 應用化學系分子科學碩博士班 === 105 === My Thesis is devoted to 2 important issues: (i) developing a set of the Slater-Koster parameters capable of reproducing accurately dihedral angle in H2O2 and simultaneously capable to predict all molecular properties of H2, O2, H2O, and H2O2 with high fidelity and (ii) assisting the development of the automatic DFTB parameterization toolkit (ADPT) by testing, reporting and locating bugs, and suggesting suitable solutions. The molecular properties of H2, O2, H2O, and H2O2 have been satisfactorily reproduced with our parameters. The optimized parameters give an error in the dihedral angle of H2O2 of −0.1 degree and simultaneously reproduce accurate equilibrium geometries for H2, O2, and H2O, with the errors smaller than 0.001 angstrom. After including the changes proposed by me, ADPT provides more flexibility to users who have no experience with DFTB parameterization and those who used to do the parameterization manually. The optimized parameters have been additionally tested against the ab initio data for water clusters. The mean absolute error for the binding energy per hydrogen bond computed with our parameters is 4.29 kcal/mol. The suggestion for improving the performance of our parameters is based on including in the reference data the energy profiles for all possible intermolecular motions in water dimer.