Erdalkalihydrogenfluoride SrF(HF2) und BaF(HF2)

Hydrogen bonded H3O+, H2O, HF, F− in fluoride metalates (Al, Cr, Fe, Zr, Ta) templated with tren (tris-(2-aminoethyl)amine)

“…Environment of (HF 2 ) À anion in [H 3 tren]Á(AlF 6 )ÁHF. The FÁ Á ÁF distances in the (HF 2 ) À anions are slightly longer than FÁ Á ÁF distances observed in KHF 2 (2.26 Å ) [21], BaHF 3 (2.27 Å ) [22], Ba 5 Nb 3 O 3 F 18 (HF 2 ) (2.21 Å ) [23] or in (1-ethyl-3-methyl)imidazolium difluoride (2.21 Å ) [24].…”

[Cu2(HF2)(H2O)8][FeF6]·2H2O

“…For other hydrated copper-iron fluorides, see: Kummer & Babel (1987); Leblanc & Ferey (1990). For FÁ Á ÁF distances, see: Frevel & Rinn (1962); Massa & Herdtweck (1983). For asymmetrical F-HÁ Á ÁF hydrogen bonding, see: Roesky et al (1990); Gerasimenko et al (2007); Gerken et al (2002).…”

“…However, if one considers the next neighbour Ow(3) at 2.715 Å as sixth ligand, thecoordination can be described as very distorted octahedral, yielding centrosymmetric, dimeric units with a Cu -Cu distance of 3.575 Å. The dimers are bonded to adjacent dimers through F(4) by a HF 2ion (figure 2), however the F -F distance (2.597 Å) is much larger (Table 2) (Massa & Herdtweck, 1983). Moreover, the hydrogen atom H(6) which would have been expected at the 1/2, 1/2, 1/2 special position, exactly at the middle of the F(4)-F(4) atoms, in order to form a linear (F-H-F) - (Roesky et al, 1990) (Gerasimenko et al, 2007).…”

Syntheses and Crystal Structures of Sodium Hydrogen Fluorides NaF·nHF (n = 2, 3, 4)

“…[14,15] The HF 2 anion in NaHF 2 is believed to be a rare case of a symmetric hydrogen bond, [16] which is also observed in KHF 2 [16] but not, for example, in CH 3 C 6 H 4 NH 3 HF 2 , [17] SrF(HF 2 ) and BaF(HF 2 ). [18] In contrast to NaHF 2 , the sodium hydrogen fluorides with higher HF content are significantly less studied. To the best of our knowledge, the first identification and visual description crystallizes in space group type Pnma with cell parameters a = 7.9276 (9), b = 3.4514(3), c = 9.6937(10) Å, V = 265.23(5) Å 3 , Z = 4 at 100 K. The investigations were complemented by IR spectroscopy and theoretical calculations.…”