Structural Study of the Molecular Complex of Antimony Trichloride with Benzene by Means of the Pure Quadrupole Resonance

Abstract

The Zeeman effect of 35Cl pure quadrupole resonance was studied on a single crystal of the 2SbCl3·C6H6 molecular complex at room temperature; it was found that the Cl–Sb–Cl bond angles of two nonequivalent SbCl3 molecules are 96.2°, 94.7°, 92.2°; 94.5°, 92.8°, and 95.2°, with an uncertainty of 1°. The asymmetry parameters for the six chlorine atoms were found to be 0.085±0.001, 0.055±0.004, 0.117±0.005, 0.119±0.005, 0.112±0.005, and 0.160±0.007, listed in the order of decreasing resonance frequencies. The bond character of the Sb–Cl bond was also calculated from the quadrupole coupling constant. It was found that the Sb–Cl bond corresponding to the lowest resonance lines in each nonequivalent SbCl3 molecule has a larger ionicity than the remainder. Moreover, the former has less of a temperature dependence than the latter. Finally, this complex may be assigned to the Ci or C1 symmetry class from the patterns of zero-splitting and from the intensity ratios of the multiplet of the spectrum.

35Cl Nuclear Quadrupole Relaxation in Antimony Trichloride

“…The corresponding 37C1 NQR lines were also ob served. The frequencies vQ agree with those reported in [6][7][8][9][10][11][12][13][14]. While the vQ of the high frequency line exhibits the usual negative temperature dependence, that of the low frequency line exhibits a much smaller dependence and below 45 K even a slightly positive dependence [10].…”

“…be x times the EFG along the primary bond, and the angle between these bonds is denoted by (p, then rj (Cl") can be expressed as a function of x and < /> . Since the average rj (Cln) is reported to be 0.15 [9,11,14,25] and 0 is calculated to be 106.9° [5], we can solve the relation for x to obtain a value of 0.106. Then the EFG's along the primary and intermolecular bonds are 1.037 and 0.110 times the largest component of the composed EFG, respectively.…”

“…3s.37c i NQR of SbCl3 has been reported by many Reprint request to Dr. N. Okubo, Institute of Physics, Uni versity of Tsukuba, Tsukuba, 305 Japan. authors [6][7][8][9][10][11][12][13][14][15]. However, these studies are limited to temperatures below 180 K or above room tempera ture, and do not deal with Tx.…”

Zeeman perturbed nuclear quadrupole spin echo envelope modulations for spin 3/2 nuclei in polycrystalline specimens

“…~ values of 0.057 and 0.153 in single crystal [18] and 0.06 and 0.16 in polycrystaUine samples [3] have been reported from steady-state NQR studies. The present experimental ZSEEM study clearly reflects the existence of a difference in the ~/ values for the two sites.…”

The crystal structure of the molecular complex between antimony trichloride and phenanthrene

“…phenanthrene has been carried out to make a contribution to understanding the nature of the interactions between the inorganic and aromatic constituents, which could be related to the donor properties of the n system of phenanthrene and to the acceptor properties of SbC13. From the study of the pure quadrupole resonance spectrum of 2SbCl3.benzene, Okuda, Nakao, Shiroyama & Negita (1968) suggested that in this compound there is a charge transfer from the n system of benzene to a chlorine atom of SbCI3, but a subsequent X-ray analysis carried out by Hulme & Szymanski (1969) showed that THE MOLECULAR COMPLEX ANTIMONY TRICHLORIDE-PHENANTHRENE the transfer of rc charge occurs to the antimony atom; this result is confirmed by the present study and by other X-ray analyses on similar compounds (Hulme, 1970).…”