The STM observations of the crystal nano-cracking phenomenon taking into account possible contribution of the edge dislocation due to the quenching of a (1 1 0) TiO2 crystal have been performed. The cleavage of a nano-particle out of the crystal as an element of the phenomenon has occurred along the (1 0 0) plane. The chosen plane of the cleavage has supported results of the theoretical calculations published by Ramamoorthy, Vanderbilt and King-Smith [Phys. Rev. B 50 (1994) 12015] and by Reinhardt and HeB [Phys. Rev. B (1994) 12015], which give considerably lower values of the surface energies of both (1 1 0) and (1 0 0) surfaces in relation to others for rutile. (C) 2003 Elsevier B.V. All rights reserved.