ESR spectra of fluorine-containing radicals of phosphorus and arsenic

Boate, A. R.; Colussi, A. J.; Morton, J. R.; Preston, K. F.

doi:10.1016/0009-2614(76)80178-9

Cited by 19 publications

(3 citation statements)

References 10 publications

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“…F • and XF n –1 •– species generated in reactions and respectively, have been identified in irradiated crystalline tetrafluoroborate and hexafluorophosphate salts. − These paramagnetic products are characterized by extended anisotropic spectra and specific high values of the hyperfine splitting constants on X atoms in XF n –1 •– (see Table ).…”

Section: Resultsmentioning

confidence: 99%

“…19 F NMR (376 MHz, methanol-d 4 ) δ 1.94 (d, J = 707.2 Hz). 31 P{ 1 H} NMR (162 MHz, methanol-d 4 ) δ −144.59 (hept, J = 707.7 Hz).…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

“…Weight of the complexes placed in alumina crucibles was ∼7 mg. NMR spectra were measured on Bruker "Avance 600" (600 MHz 1 H, 151 MHz 13 C) and Bruker "Avance 400" (376 MHz 19 F, 162 MHz 31 P). The 1 H chemical shifts were referenced to the residual undeuterated solvent peak, 13 C chemical shifts were referenced to the solvent peak, 19 F NMR chemical shifts were referenced to external standard CF 3 CO 2 H (0.0 ppm), and 31 H 3 PO 4 (0.0 ppm). FTIR spectra were measured using Nicolet iS50FT-IR spectrometer in the range 4000−400 cm −1 with a resolution of 2 cm −1 .…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

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Evidence for Indirect Action of Ionizing Radiation in 18-Crown-6 Complexes with Halogenous Salts of Strontium: Simulation of Radiation-Induced Transformations in Ionic Liquid/Crown Ether Compositions

et al. 2018

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Ionic liquid/crown ether compositions are an attractive alternative to traditional extractants in the processes for spent nuclear fuel and liquid radioactive wastes reprocessing. These compositions are exposed to ionizing radiation, and their radiation stability, especially in the presence of metal salts, is a crucial issue. In the present study, the macrocyclic 18C6·Sr(BF) and 18C6·Sr(PF) complexes simulating the components of metal loaded ionic liquid/crown ether extractants were synthesized and their structures were characterized by FTIR spectroscopy and single-crystal X-ray diffraction analysis. Inclusion of Sr cation into the 18C6 cavity resulted in more symmetric D conformations of the macrocycle. The structural transformations of the crown ether were accompanied by an elongation of polyether C-O bonds that could increase the possibility of radiolytic cleavage of the macrocycle. However, EPR study of the synthesized compounds subjected to X-ray irradiation revealed predominant formation of macrocyclic -CH-ĊH-O- radicals. This result demonstrated an evidence for indirect action of ionizing radiation on individual components of the complexes and was reasonably described by a positive "hole" transfer from primary macrocyclic radical cation to fluorous anion at the primary stages of radiolysis and a subsequent interaction of fluorine atom with 18C6 macrocycle in secondary radical reactions. The observed effects may be partially responsible for enhanced sensitivity of the ionic liquid/crown ether extractants to ionizing radiation due to chemical blocking of the crown ether with radiolytic HF, radiation-chemical degradation of the 18C6, and precipitation of a low-soluble SrF.

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