H/D isotope effects on the low-temperature NMR parameters and hydrogen bond geometries of (FH)₂F⁻and (FH)₃F⁻dissolved in CDF₃/CDF₂Cl

[FHF]−—The Strongest Hydrogen Bond under the Influence of External Interactions

“…However these distances are observed in the [FHF] − …HF complex. This complex was observed in earlier studies [27][28][29] and is also analyzed here; it possesses C2v symmetry and may be considered as the F3H2 − anion. The (MP2/aug-cc-pVTZ level) F-H and H…F distances calculated here for this complex are equal to 1.008 and 1.343 Å, respectively (Table 1) which is in agreement with the previous MP2/6-31+G** calculations where 1.012 and 1.349 Å distances were found [27].…”

“…(HF) 2 cluster on the other hand. Such a system has been analyzed previously both experimentally and theoretically [27][28][29].…”

“…There have been earlier studies where the symmetric and asymmetric hydrogen bifluoride anions were considered [26][27][28][29][30][31][32][33][34][35][36][37]. However in this study the emphasis is put on electron charge redistribution being the result of complexation.…”

“…Figure 5 presents also the continuous line passing through the points corresponding to the hydrogen bifluoride anions possessing D 8h and C 2v symmetries; theoretical results are presented (free [FHF]´anion and its complexes with Na + , Li + cations) as well as species found in the crystal structures. [27][28][29] and is also analyzed here; it possesses C 2v symmetry and may be considered as the F 3 H 2´a nion. The (MP2/aug-cc-pVTZ level) F-H and H .…”

A review with comprehensive data on experimental indirect scalar NMR spin–spin coupling constants across hydrogen bonds

“…[62] Using the q 1 parameter they found smooth variations of the coupling constants, which could be adjusted to exponential models related to valence bond orders p FH . In this way, they were able to estimate a 1 J FH • = 600 Hz for a hypothetical free HF dissolved in the Freon mixture and the missing 2 J FF • of Table 16 for [FHF] − to be 225 Hz.…”