Au-nanoparticles have volume effect, surface effect, quantum size effect, macroscopic quantum tunneling effect and other excellent properties. In addition, there are some special properties for Au-nanoparticles, such as good stability, antibacterial function, surface absorption, fluorescence effect belt and so on. Quantum chemistry calculation provides a method to investigate the factors that affect the catalytic and reactive activity of gold clusters at the molecular level, such as the gold cluster size, shape, electronic state, active site and structure, etc. The interaction modes of nanoparticles with ligands and solvent can be better simulated by molecular dynamics, which can also give the behavior of thermodynamic and kinetic. Dissipative particle dynamics mesoscopic simulation method is applied to study the self-assembly process of Au-nanoparticles and polymer composite system, which would be an effective scheme to control the self-assembled structure. To clear the dominant factors influencing the complex structure and properties, to explore the complex regulation mechanism, to propose the main control factors, which is good for the further understanding the nature of Au-nanoparticles and polymer composite system. It is also providing a reliably theoretical help for experiments to prepare and optimize the new kinds of composite materials.

Contents
1 Introduction
1.1 Au-nanoparticles
1.2 Polymers
2 Computer simulation methods
2.1 Quantum chemistry,QC
2.2 Molecular dynamics,MD
2.3 Brownian dynamics,BD
2.4 Dissipative particle dynamics,DPD
3 Assembly of Au-nanoparticles and polymer composites
3.1 Au-nanoparticles and homopolymer
3.2 Au-nanoparticles and copolymer
4 Conclusion