An investigation of the quadrupole coupling of two N nuclei in the complex pyrimidine–Ar by molecular beam Fourier transform microwave spectroscopy

• Published in: Journal of molecular structure Vol. 612; no. 2; pp. 393 - 399
• Main Authors: Maris, A, López, J.C, Alonso, J.L, Caminati, W
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 17-07-2002
• Subjects: Ab initio calculations; Free jets; Quadrupole coupling; Rotational spectroscopy; Van der Waals complexes; Free jets; Van der Waals complexes; Quadrupole coupling; Ab initio calculations; Rotational spectroscopy
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/S0022-2860(02)00148-5

The quadrupole coupling hyperfine structure of two equivalent
14N nuclei in the rotational spectrum of pyrimidine–Ar complex has been investigated in the range of 6–18
GHz using molecular beam Fourier transform microwave spectroscopy. From the analysis of the hyperfine structure the elements
χ
aa
,
χ
bb
,
χ
cc
and
χ
bc
of the quadrupole coupling tensors in the principal inertial axis system of the complex have been determined. A comparison of the quadrupole constants of the complex with those of bare pyrimidine indicates that these constants are consistent with the structure of the complex previously reported, with the Ar atom tilted ca. 5° towards the two N atoms. This configuration is supported by ab initio calculations.