The rotational spectrum, structure, and molecular properties of the ethylene–HCl dimer

Abstract

The rotational spectrum and molecular structure of the furan-HCl complex J. Chem. Phys. 78, 3545 (1983); 10.1063/1.445178The rotational spectrum and molecular structure of the ethylene-HF complex J. Chem. Phys. 76, 4857 (1982); 10.1063/1.442804The rotational spectrum and molecular structure of the acetylene-HCl dimer J. Chem. Phys. 75, 625 (1981); 10.1063/1.442079Microwave rotational spectrum, molecular geometry, and intermolecular interaction potential of the hydrogen bonded dimer OC-HCl Three isotopic species of a hydrogen bonded dimer formed between ethylene and HCI have been observed through assignment of their rotational spectra using a pulsed. Fourier transform microwave spectrometer in which a gas mixture is pulsed into an evacuated Fabry-Perot cavity. The spectra unambiguously reveal a nonplanar. near prolate. asymmetric top (K = -0.9880) in its ground vibrational state. The equilibrium structure has C 2V symmetry with the HCI on the C 2 symmetry axis of the dimer. perpendicular to the carbon-carbon bonding axis with the hydrogen atom located between the chlorine and the ethylene molecule. pointing midway between the carbon atoms. The chlorine atom is situated. on average. 3.724 A from the edge of the ethylene molecule. The following spectroscopic constants have been obtained for the ethylene-H"CI dimer: the rotational constants are A = 25 457(349). B = 2308.143(3). and C = 2167.970(3) in units of MHz; the chlorine nucleus quadrupole coupling constants are Xaa = -54.076(4). Xbb = 27.091(6). and X" = 26.985(10) in units of MHz. and the centrifugal distortion constants are D J = 7.2(2) and DJK = 282(5) in units of kHz. 2126

General features of geometries and potential constants of hydrogen bonded dimers

“…Consistent with the lone-pair model, it has a nonlinear geometry, with an angle of 70" between the axis of the HF acceptor and HF donor [ 191. Finally where no electron lone-pairs are present, but r-bonding pairs are, the observed geometries are consistent with a model in which the hydrogen donor seeks the region of maximum electron density in the r bond of B [20].…”

Infrared spectra of the hydrogen-bonded pi complex C2H4–HF in solid argon

“…Codeposition of Ar/C 2 H 4 = 200/1 and Ar/HCl = 100/1 mixtures produced bands at 2751 cm-1 (A=0. 19) and at 957.5 cm-1 (A=0.05). …”

Defining the hydrogen bond: An account (IUPAC Technical Report)

“…With the advent of cryogenic matrices [110] and supersonic beams [111] for producing exotic species, there have been several reports of hydrogen-bonded complexes involving HCl [112,113] and H 2 S [114,115]. Moreover, it has been shown recently that on increasing the pressure and decreasing the temperature, H 2 S has a structure similar to that of H 2 O in ice [116].…”