NYU CHEMISTRY DEPARTMENT 

RESEARCH - Crystal Structure Animations

Real-time growth of proximal screw dislocations on the (001) surface of the hexagonal form of L-cystine, as viewed with atomic force microscopy.

Real-time growth of screw dislocation on the (010) surface of calcium oxalate monohydrate, as viewed atomic force microscopy.

Real-time growth of knife-shaped terraces on the (12-1) surface of calcium oxalate monohydrate, as viewed with atomic force microscopy.

Real-time growth of a screw dislocation on the (100) surface of calcium oxalate monohydrate, as viewed with atomic force microscopy.

Real-time growth of a screw dislocations on the (001) surface of the hexagonal form of L-cystine, as viewed with atomic force microscopy. Note the clockwise rotation of the spiral. The screw dislocation with a Burger vector magnitude of 5.6 nm (equivalent to the c lattice parameter, which spans six L-cystine molecules winding around a 6(1) screw axis) splits into six dislocations, each with a magnitude pf 0.94 nm. This is expect from classical dislocation theory.

Real-time growth of proximal screw dislocations on the (001) surface of the hexagonal form of D-cystine, as viewed with atomic force microscopy. Note the counter-clockwise rotation of the spiral, which is opposite to the direction observed for L-cystine. Like L-cystine, screw dislocation with a Burger vector magnitude of 5.6 nm splits into six dislocations, each with a magnitude pf 0.94 nm.

WARD GROUP