Analysis of results obtained in a molecular dynamics simulations can bea painstaking process for complex systems of realistic sizes. To facilitate an intelligent analysis of the global properties of the system under study in terms of its local enviroment, we have developed powerful local analysis tools that can be used in conjunction with the molecular dynamics simulation. These local analysis tool are very flexible and can be applied to a variety of situations. For example, (i) In the crack nucleation of a solid under hydrostatic tension, we use spatial and dynamical measures of the bond instability; the spatial measure can be used to pinpoint the location of lattice instability while the dynamical measure identifies the vibrational modes which are responsible for the formation of crack in solid, and (ii) to understand the trends of chemical reacitivity in silicon clusters of different sizes, we have examined local electronic properties of the system. It has been demonstrated that the interplay of local energetics electron occupanciesm and local electronic densities of states is the key to the understanding of the chemical reactivity.
