Hydrogen bond studies. XIV. The crystal structure of ammonium acetate

The crystal and molecular structures of ammonium fluoroacetate, C2H6FNO2, and ammonium difluoroacetate, C2H5F2NO2

“…The suggestion was made that the hydrogen-bond N... O distances in (IV) are longer than in (I) because the greater electronegativity of the -CF 3 group relative to -CH3 makes the O atoms less negative (Nahringbauer, 1967). As shown in Table 6, the N. • • O distances in (I), (II), (Ill) and (IV) do not correspond closely to the number of F atoms; this indicates that the effective electronegativity of the O atoms is not the major factor affecting N... O distances in these structures.…”

“…The crystal and molecular structure determinations of ammonium fluoroacetate (1I) and ammonium difluoroacetate (III) were undertaken to further elucidate the results from the ESR studies, to reveal the hydrogen-bonding networks in the crystals, and to complete the series of fluoro derivatives of ammonium acetate [ammonium acetate (I), Nahringbauer (1967), and ammonium trifluoroacetate (IV), Cruickshank, Jones & Walker (1964)]. …”

The crystal and molecular structure of the 1:1 addition compound of piperidine with p-toluic acid, piperidinium p-toluate

“…As shown in Table 4, the hydrogen bond lengths of these compounds are substantially identical and no effect due to the electron withdrawing properties of the substituents, such as has been observed in the case of ammonium trifluoroacetate and ammonium acetate (Nahringbauer, 1967), is discernible. This is probably because the intermolecular contacts are so close that more short hydrogen bonds cannot be allowed.…”

“…It may be seen that the C-N...O angles are tetrahedral in nature, as found in other N+-H -. -O-hydrogen bond systems, for example ammonium trifluoroacetate (Cruickshank, Jones & Walker, 1964), ammonium acetate (Nahringbauer, 1967), hexamethylenediammonium adipate (Hirokawa, Ohashi & Nitta, 1954), ~-glycine (J6nsson & Kvick, 1972) and nicotinyl salicylate (Kim & Jeffrey, 1971). The deviations from the regular tetrahedral angle in these compounds range within 15 °.…”

The structure of tetraaqua(2,2,3,3-tetrafluorosuccinato)zinc(II)

“…These angles are significantly greater than the O-C-O angles observed in metal complexes of the corresponding H-substituted ligand, succinate, where the range is 117 (3) to 124.7(9) ° (Karipides & Reed, 1980). A similar opening of the O-C-O angle occurs in going from acetates to various fluoroacetates (Wei & Ward, 1976;Macdonald, Speakman & Hadzi, 1972;Curie, 1972;Nahringbauer, 1967;Cruickshank, Jones & Walker, 1964).…”