research papers
The title structures have been redetermined in order to improve the structural data of the rhombohedral series of group 1 rare earth sulfides. The observed dependence of the fractional coordinate z(S2−) on the identity of the rare earth element in the newly determined structures is in agreement with the known structures of the potassium and rubidium analogues.
research papers
In 2-amino-1,3,4-thiadiazolium hydrogen oxalate, 2-amino-1,3,4-thiadiazole–glutaric acid (1/1) and 2-amino-1,3,4-thiadiazole–adipic acid (1/1), the graph-set motifs (8), with N—HO and O—HN hydrogen bonds of moderate strength, are the most prominent features (N—HO hydrogen bonds are present only in 2-amino-1,3,4-thiadiazolium hydrogen oxalate). The hydrogen-bond pattern of 2-amino-1,3,4-thiadiazole–succinic acid (1/2) differs considerably from the other title structures, though N—HO and O—HN hydrogen bonds of moderate strength are also present. There are nonbonding SO interactions in all four structures, however, the packing patterns are quite different.
research papers
The second-order phase transition in 4-chloro-3-nitroaniline and 4-iodo-3-nitroaniline is characterized by the single-crystal X-ray structure determination of the respective isostructural phases as well as by Raman spectroscopy and differential scanning calorimetry.