On September 1, 2009, Yang, Limin; Zhao, Guozhong; Li, Weihong; Liu, Yufeng; Shi, Xiaoxi; Jia, Xinfeng; Zhao, Kui; Lu, Xiangyang; Xu, Yizhuang; Xie, Datao; Wu, Jinguang; Chen, Jia’er published an article.Safety of Pyridine-3-sulfonic acid The title of the article was Low-frequency vibrational modes of DL-homocysteic acid and related compounds. And the article contained the following:
Several polycrystalline mols. with sulfonate groups and some of their metal complexes, including DL-homocysteic acid (DLH) and its Sr- and Cu-complexes, pyridine-3-sulfonic acid and its Co- and Ni-complexes, sulfanilic acid and -cysteic acid were studied using THz time-domain methods at room temperature The results of THz absorption spectra show that the mols. have characteristic bands at 0.2-2.7 THz (6-90 cm-1). THz technique can be used to distinguish different mols. with sulfonate groups and to determine the bonding of metal ions and the changes of H bond networks. In the THz region DLH has three bands: 1.61, 1.93 and 2.02 THz; and 0.85, 1.23 and 1.73 THz for Sr-DLH complex, 1.94 THz for Cu-DLH complex, resp. The absorption bands of pyridine-3-sulfonic acid are located at 0.81, 1.66 and 2.34 THz; the bands at 0.96, 1.70 and 2.38 THz for its Co-complex, 0.76, 1.26 and 1.87 THz for its Ni-complex. Sulfanilic acid has three bands: 0.97, 1.46 and 2.05 THz; and the absorption bands of -cysteic acid are at 0.82, 1.62, 1.87 and 2.07 THz, resp. The THz absorption spectra after complexation are different from the ligands, which indicate the bonding of metal ions and the changes of H bond networks. M-O and other vibrations appear in the FIR region for those metal-ligand complexes. The bands in the THz region were assigned to the rocking, torsion, rotation, wagging and other modes of different groups in the mols. Preliminary assignments of the bands were carried out using Gaussian program calculation The experimental process involved the reaction of Pyridine-3-sulfonic acid(cas: 636-73-7).Safety of Pyridine-3-sulfonic acid
The Article related to frequency vibrational mode homocysteic compound, Optical, Electron, and Mass Spectroscopy and Other Related Properties: Vibrational and Rotational Spectroscopy and other aspects.Safety of Pyridine-3-sulfonic acid