Crystal data for some guanidinium salts

Several guanidinium salts have been studied since, because they contain six hydrogen atoms per unit charge, they are likely to contain multiple hydrogen bonding systems [see e.g. Adams & Small (1974). Acta Cryst. B30, 2191–2193], which are of interest in themselves and are also likely to cause stabilization of the structure. The crystal data of a range of salts were collected and are given. Space group and approximate cell dimensions were obtained from oscillation and Weissenberg photographs. Powder diffraction data [0° to 60° (2θ using Cu Kα)] were indexed and the cell parameters refined using the programs PIRUM of Werner [Program No. 1, World List of Crystallographic Computer Programs (3rd. ed.): J. Appl. Cryst. (1973). 6, 309–346] and CELFIT of Bracher [UKAEA Research Report, AERE-R5412 (1967)].