Triethylammonium halides, Et₃NHX (X = Cl, Br, I): simple structure, complex spectrum

Abstract

A crystal structure determination has shown that the ethyl groups in the three isostructural (P63mc, Z = 2) triethylammonium halides, Et3NHX (X = Cl, Br, I), at room temperature are orientationally disordered and the [Formula: see text] groups are linear by symmetry. The unusual extent and complexity of the NH and ND stretching absorptions in the ir spectra of all three compounds between 10 and 293 K are discussed in terms of Fermi resonance interactions. The centroid ν(NH) and ν(ND) frequencies extracted from the spectra correlate with the [Formula: see text] distances. It is shown that if Fermi resonance is the sole cause of the complexity of the stretching absorptions, then these centroids represent the ν(NH) and ν(ND) frequencies unperturbed by Fermi resonance. The centroid frequencies in the three halides are unusually low, pointing to strong [Formula: see text] hydrogen bonding.

The lone electron pair and crystal packing: observations on pyramidal YEL3ε species, abinitio calculations, and the crystal structures of Me3SOI, Et3SI, (Me3S)2SnCl6, (Me3SO)2SnCl6, and (Et3S)2SnCl6

“…In Fig. 2 (16,17), and K2SO3 (34) compared with the orientations of the SO, PO, NH, and NC bonds in Me3SOI (this work), POBr3 (42,43), Me3NHI (58), Et3NHI (59), and Me4NI (1 1). The central atom of the trigonal-pyramidal grouping is S, Se, N, P, or C1; the axis is oriented vertically in the page.…”

Crystal chemistry of tetraradial species. Part 2. Crystal structures of Et4NI, Ph4PBr•H2O, and Ph4PBr•2H2O

“…In the other cases it is 0.26 A or less out of the plane of the ring. (16) anion in the monohydrate is only 94.7". Whether this rather small angle and the rather long O...Br-distances are attributable to the bulkiness of the cation cannot be ascertained at present.…”

Organometallic Supramolecular Chemistry with Monosaccharides: Triethylammoniumμ-Chloro-bis{chloro(η5-cyclopentadienyl)(methyl 4,6-O-benzylidene-β-D-glucopyranosidato-1κO2,1:2κO3)zirconate}

“…The nonbonding distance between N and Cl1 amounts to 323.3(2) pm, and is slightly longer than the corresponding NÀCl distance in [Et 3 NH]Cl (310.7 pm). [19] The elongation of the N´´´Cl1 distance in 2 compared with free [Et 3 NH]Cl may be explained by the interaction of the proton with the Zr-bound chloro ligand in 2, whereas in [Et 3 NH]Cl the hydrogen bonding occurs with a free chloride anion.…”