JOURNAL-OF-CRYSTAL-GROWTH. MAR 1999; 199 Part 1 : 246-252

The centers of several growth spirals on. the dominant {1 1 1} and {1 0 0} faces of Ba(NO3)(2) crystals grown from aqueous solutions were investigated using ex situ atomic force microscopy. On both faces, often hollow cores were observed, at the outcrops of dislocations with Burgers vectors b = < 1 0 0 > on the {1 0 0} face, and b = < 1 0 0 >, < 1 1 0 > and (1 1 1) on the (1 1 1) face. The occurrence of the hollow cores depends on the supersaturation. For the (1 1 1) face, the dependence of the hollow core radius on the Burgers vector is measured. This observed dependence is less strong than the quadratic dependence expected from the Frank radius, which is explained by the influence of the supersaturation. Apart: from that, recombination of two dislocations, leaving the hollow cores on the original positions has been observed.