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Analysis of Ion Species Formation in HF Mass Spectra

This analysis examines the formation of ion species in HF mass spectra, focusing on the relevant ion species observed. The study considers the coefficient values and concludes that the formation occurs via radical reactions. The findings suggest that the ion signals increase as HF is diluted, indicating the formation of ions after excitation of oligomers. Further investigation reveals the possibility of C2 or C2H formation from (HF)2.

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Analysis of Ion Species Formation in HF Mass Spectra

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  1. Analysis, 200707 : Mw1 91 1 12 245 3.4641 13 254 3.60555 14 262 3.74166 15 271 3.87298 24 335 4.89898 25 341 5 26 347 5.09902 27 354 5.19615 28 359 5.2915 32 382 5.65685 33 388 5.74456 34 393 5.83095 pnt Sqrt(Mw) “agust, heima../HF/mass calibr-200707ak.ppt”

  2. pnt Coefficient values ± one standard deviation a = 28.432 ± 0.321 b = 62.538 ± 0.0686 Sqrt(Mw)

  3. Wave7 vs pnt; 200707 From “agust,heima.. /HF/fra Wang/ Pure HF 1 bar mass-190707.pxp” pnt

  4. conclusion

  5. 37Cl+ H35Cl+ Conclusion relevant to ion species observed: H37Cl+ 35Cl+ H+ C2FH4+ CH3+ C2FH3+ C2H5+ C2FH2+ C2H4+ C2FH+ C+ CH2+ C2H3+ CH+ C2H2+ CFH3+ C2H+ CFH2+ CFH+ Wave7 vs pnt; 200707 From “agust,heima.. /HF/fra Wang/ Pure HF 1 bar mass-190707.pxp” Skimmer out C2+ pnt

  6. Comments: • Most probably the ion species (and the F containing species in particular) are formed via radical • reactions, such as between F and oil (CxHy), for example: • F + CxHy ->->-> C2,. ...CFH,... Followed by • N hv + C2,...CFH... ->-> C2+,...CFH+ • F can not be formed by 2 hv excitation of the monomer in this region (see : e-mail 5.6.07 • (http://www.hi.is/~agust/rannsoknir/rempi/hf/REMPI%20signal.txt) and • http://www.hi.is/~agust/rannsoknir/rempi/hf/HF-pot-090307.ppt and EJ calculations (http://www.hi.is/~agust/rannsoknir/rempi/hf/EJ-080307.xls) ) • The ion signals increase as HF is diluted according to KM (e-mail 12.06.07 / agust,heima,.. • /REMPI/HF/KM/Massspectra vs %HF-120607.pxp) • Hence probably F is formed after excitation of oligomers (dimer): • (HF)n + 2hv -> (HF)n* followed by dissociation, such as: • (HF)n* -> F + ... (which is what Andras Bodes calculations suggest • (http://www.hi.is/~agust/rannsoknir/rempi/hf/PES-011106.pdf)! • -in which case these signals are measurements of (HF)n !!!!

  7. Comments: Furthermore: the “HF)2” signal recorded in 2005 is in fact a mass near 24 – 26 (see e-mail from me to Wang and KM 190707) and could be C2 or C2H formed as: (HF)2 + 2 hv ->-> F or H F + C2H2 -> HF + C2H Followed by C2H + n hv ->-> C2H+ NB!: C2H2 had been used on the vacuum line before we did the HF experiments

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