2887-09-4Relevant articles and documents
Identification of Degradation Products of Sea-Dumped Chemical Warfare Agent-Related Phenylarsenic Chemicals in Marine Sediment
Kiljunen, Harri,Niemikoski, Hanna,Ostin, Anders,Soderstrom, Martin,Vanninen, Paula
, p. 4891 - 4899 (2020/08/07)
Previously unknown phenylarsenic chemicals that originated from chemical warfare agents (CWAs) have been detected and identified in sediment samples collected from the vicinity of chemical munition dumpsites. Nontargeted screening by ultrahigh-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) was used for detection of 14 unknown CWA-related phenylarsenic chemicals. Methylated forms of Clark I/II, Adamsite, and phenyldichloroarsine were detected in all analyzed sediment samples, and their identification was based on synthesized chemicals. In addition, other previously unknown CWA-related phenylarsenic chemicals were detected, and their structures were elucidated using MS/HRMS technique. On the basis of relative isotope ratios of protonated molecules and measures of exact masses of formed fragment ions, it could be concluded that some of these unknown chemicals contained a sulfur atom attached to an arsenic atom. In addition to that, some of the samples contained chemicals that had formed via addition of an OH group to the aromatic ring. However, it is not possible to say how these chemicals are formed, but the most plausible cause is activities of marine microbes in the sediment. To our knowledge, these chemicals have not been detected from sediment samples previously. Sensitive analytical methods are needed for these novel chemicals to assess the total CWA burden in marine sediments, and this information is essential for the risk assessment.
Ground Term Splitting of High-Spin Co(2+) as a Probe of Coordination Structure. 1. Dependence of the Splitting on Coordination Geometry
Makinen, Marvin W.,Kuo, Lawrence C.,Yim, Moon B.,Wells, Gregg B.,Fukuyama, James M.,Kim, Judy E.
, p. 5245 - 5255 (2007/10/02)
The sign and magnitude of the splitting between the two lowest Kramers doublets (Δ) of high-spin Co(2+) in a variety of structurally defined, small molecule coordination complexes is determined.The range of values of Δ is found to be -1 in tetracoordinate sites, ca. 20-50 cm-1 in pentacoordinate sites of trigonal-bipyramidal or square-pyramidal geometry, and 50 cm-1 in hexacoordinate sites.It is shown on the basis of group theoretical arguments and estimates of the zero-field splitting derived by second-order perturbation theory that the observed range of values of Δ correlates well with that predicted by theory.On this basis, it is suggested that the splitting between the two lowest Kramers doublets of high-spin Co(2+) may provide a diagnostic signature of coordination geometry.
