title: Comparative study of analytical properties and applications of picolinaldehyde thiosemicarbazone and selenosemicarbazone.
abstract: The analytical properties of picolinaldehyde thiosemicarbazone and selenosemicarbazone have been studied, in order to investigate the changes produced when the Se atom is substituted for the S atom. The ionization constants of both substances are very similar. The complexes of picolinaldehyde selenosemicarbazone with cations in aqueous solution are less stable, and the absorption spectra show bathochromic and hypochromic shifts. The introduction of the Se atom offers no advantages in the analytical application of these compounds.
authors.affiliation: Department of Analytical Chemistry University of Seville Seville, Spain.
authors.forename: J M
authors.initials: JM
authors.lastname: Pavon
authors.forename: F
authors.initials: F
authors.lastname: Pino