Observation of Astatine Compounds by Time-of-Flight Mass Spectrometry

The bonding picture in hypervalent XF3 (X = Cl, Br, I, At) fluorides revisited with quantum chemical topology

“…The effective core potential (ECP)‐based spin‐orbit DFT method was selected for the 2c‐DFT computations which handle on an equal footing electron correlation and SOC during the variational treatment. The applied density‐functional approximation is the PBE0 hybrid functional, whose applicability was recently assessed on the XF 3 systems under study . For the ClF 3 system, only all‐electron NR‐DFT calculations were performed while SR‐DFT and 2c‐DFT computations were performed on the remaining systems using small‐core ECP n MDF pseudopotentials.…”

“…The applied density-functional approximation is the PBE0 hybrid functional, [51] whose applicability was recently assessed on the XF 3 systems under study. [8,52] For the ClF 3 system, only all-electron NR-DFT calculations were performed while SR-DFT and 2c-DFT computations were performed on the remaining systems using smallcore ECPnMDF pseudopotentials. The pseudopotentials that overcome the absence of the n 5 10, 28, and 60 inner-core electrons have been used for the Br, I, and At atoms, respectively.…”

“…Moreover, a structure of the same type is predicted by numerous quantum mechanical calculations for the AtF 3 analogue, even if this has not yet been experimentally confirmed. In contrast to chlorine, bromine or iodine fluorides, the attempts to form astatine fluorides turned out to be unsuccessful . Thus, quantum mechanical computations are very useful to gain a better knowledge of such astatine systems.…”

“…In contrast to chlorine, bromine or iodine fluorides, the attempts to form astatine fluorides turned out to be unsuccessful. [8] Thus, quantum mechanical computations are very useful to gain a better knowledge of such astatine systems. Interestingly, AtF 3 appears as a borderline system as a planar D 3h local-minimum structure is also predicted, which is almost isoenergetic with the T-shaped one.…”

Which halogen is the strongest oxidant? A study with systematics and surprises

“…We know of no classical chemistry for any astatine counterparts; astatine is an artificial element with a half-life of 7.5 h and is too radioactive for many plausible studies to have been performed. AtCl, AtBr and AtI have been observed using mass spectrometry [24] and thermochromatography [25]. AtF and other astatine fluorides remain uncharacterized in the experimental primary chemical literature [26] (this is mainly due to astatine radioactive decay and short lifetime, perhaps also because these last species are too involatile to have been observed by the employed techniques).…”