Atomic force microscopy studies on growth mechanisms of LAP crystals grown in solution containing excessive amount of l-arginine

Atomic force microscopy (AFM) has been used to investigate the growth mechanisms of the l-arginine phosphate monohydrate (LAP) crystal grown from the aqueous solution containing excessive amount of l-arginine molecules. Under this condition, the LAP crystals grow by both 2D nucleation mechanism and spiral dislocation mechanism. 2D nucleation growth is the intrinsical growth mechanism owing to the crystal structure of LAP. The spiral growth mechanism probably results from the distortion of the crystal lattices produced by the LAnP unit or separated l-arginine molecule. Pinning points of impurities and curved step type induced by them are also explored.