An investigation of the rotational spectrum of H2S⋅⋅⋅HF by pulsed‐nozzle, Fourier‐transform microwave spectroscopy: Determination of the hyperfine coupling constants χaa(33S), χDaa, andDH(D)Faa

1984 ◽  
Vol 81 (1) ◽  
pp. 20-26 ◽  
Author(s):  
L. C. Willoughby ◽  
A. J. Fillery‐Travis ◽  
A. C. Legon

The ground state rotational spectrum of a hydrogen-bonded heterodimer formed from water and hydrogen cyanide has been detected and measured by using the technique of pulsed-nozzle, Fourier-transform microwave spectroscopy. Rotational constants ( B 0 , C 0 ) centrifugal distortion constants ( ∆ J , ∆ JK ) and, where appropriate, 14 N-, D- or 17 O-nuclear quadrupole coupling constants have been determined for the following isotopic species; H 2 16 O· · · HC 14 N, H 2 18 O· · · HC 14 N, H 2 16 O· · · HC 15 N, HD 16 O· · · HC 15 N, D 2 16 O· · · HC 15 N, H 2 16 O· · · DC 15 N, HD 16 O· · · DC 15 N and H 2 17 O· · · HC 15 N. An analysis of these spectroscopic constants indicates that the heterodimer is effectively planar, with a pair of equivalent protons and the arrangement H 2 O· · · HCN. The intermolecular interaction is through a hydrogen bond between HCN and H 2 O and the distance between the O and C nuclei r (O· · · C) is 3.157 Å (1Å = 10 -10 m). An interpretation of the nuclear quadrupole coupling constants leads to the conclusion that arccos <cos 2 Φ > ½ ≈ 51°, where Φ is the angle between the local C 2 axis of H 2 O and the a -axis of the complex; and that arccos <cos 2 θ > ½ ≈ 10°, where θ is the angle between the HCN axis and the a -axis. The intermolecular stretching force constant k σ = 11 Nm -1 has been determined from ∆ J .


1996 ◽  
Vol 51 (10-11) ◽  
pp. 1099-1106 ◽  
Author(s):  
Holger Hartwig ◽  
Helmut Dreizler

Abstract We used the advanced technique of Fourier transform microwave spectroscopy to measure and assign the ground state rotational spectrum of anti-2,3-dimethylthiirane, and to analyse the internal rotation of the two methyl groups. The potential parameters obtained are V3 = 13.1678(21) and V12' = -1.6678(25) kJ/mol. The measurement and assignment of the 13C and 34S isotopomers in the ground state allowed to determine the molecular structure of the heavy atom frame using the Τs and Τ0 methods.


1995 ◽  
Vol 50 (7) ◽  
pp. 666-668 ◽  
Author(s):  
U. Kretschmer

The rotational spectrum of the 33S dimethylsulfoxide in natural isotopic abundance has been studied using molecular beam Fourier transform microwave spectroscopy. Rotational and quadrupole coupling constants could be extracted from the spectra. They were found to be A = 7017.5456(16) MHz, B = 6894.5117(17) MHz, C=4218.14115(84) MHz, χaa-15.720(18) MHz, χbb= -17.045(23), and χcc = 32.765(25) MHz.


1993 ◽  
Vol 48 (12) ◽  
pp. 1219-1222 ◽  
Author(s):  
U. Kretschmer ◽  
H. Dreizler

Abstract We investigated the 33S nuclear quadrupole coupling of thiazole- 33S in natural abundance by molecular beam Fourier transform microwave spectroscopy. In addition the 14N nuclear quadrupole coupling could be analyzed with high precision. We derived the rotational constants A = 8529.29268 (70) MHz, B = 5427.47098 MHz, and C = 3315.21676 (26) MHz, quartic centrifugal distortion constants and the quadrupole coupling constants of 33S χaa = 7.1708 (61) MHz and χbb= -26.1749 (69) MHz and of 14N χ aa = -2.7411 (61) MHz and χbb = 0.0767 (69) MHz.


Sign in / Sign up

Export Citation Format

Share Document