Atom collocation method

This paper presents a new concurrent atomistic-continuum method called the atom collocation method (ACM). By adopting the framework of continuum collocation method, ACM aims at overcoming the current difficulties in interfacial mismatch, adaptive analysis, and parallel implementation of existing atomistic-continuum methods. The proposed ACM is truly meshfree and generalizes the full atomistic description, which naturally yields a perfectly compatible atomistic/continuum interface that eliminates any ghost forces. A unique feature of ACM is that the collocation atoms can be turned on or off freely at any time without the need to reconstruct interpolation functions, which greatly enhance the ability to perform adaptive analysis. The proposed ACM is applied to solve problems involving point defect and crack propagation as well as surface, edge, and corner effects and demonstrates excellent accuracy and efficiency compared to molecular statics.