In this project, we will continually focus on the study of nano-electronics and photonics through first-principles simulations. Specifically, we will develop an efficient algorithm for the general Raman polarizability in the linear response theory framework, studying the plasmonic effect on novel optical response of molecules in nano-cavity. The high-precision simulations will not only help us to understand the fundamental of many emerging phenomena on nanoscale but also lead to important theoretical predictions such as the unique monitor ability in hydrogen tautomerization of single porphine molecule by localized plasmonic field. We will also focus on the mechanisms of isomerization for the representative azobenzene molecule with the complete isomerization pathway searching and thus benefit the rational design of molecule switch for the further nanotechnology. The large-scale first principle simulations based on Maxwell equations, time-dependent perturbation theory, the density matrix equations, and multi-configurational quantum chemistry methods are employed in all these projects, which requires heavy computations. The progress of the project will depend severely on the sufficient computational resources.