Abstract
Ab initio calculations as well as density functional theories are utilized to study chemical spectroscopy and global potential surfaces with numerical methods. The subjects cover the first ionization energy of sulfenyl chlorides by Gaussian-2 scheme, the ionization energies of alkyl halides and corresponding alkenes with designated single-configuration complete active space self-consistent field (DSCCAS) method, the fitting for analytical expressions of the global potential energy surfaces of ground-state CH2, and the theoretical spectra of electroluminescent polymers as the poly(p-phenylene vinylene) and its derivatives. The final topic describes recent advances in the electronic structure calculations with modern hardware and software as well as optimized compilers and numerical libraries on personal computers.