114
SHARUTIN et al.
relative elongation of the Sb–X bond in Ph4SbX com-
S
pounds and the strength of HX acid, which was esti-
mated from the value of Kα, is not always fulfilled. For
example, the strength of thiocyanic acid (Kα = 0.85
[17]) is considerably lower than that of hydrohalic
acids, whereas the relative elongation of the Sb–X bond
in compound III is the same as that in VII. Second, the
distortion of a trigonal-bipyramidal coordination of the
Sb atom also does not depend on the strength of HX
acid, whose residue is X ligand (compare the geometric
parameters of III and VII). Hence, the use of Kα in
estimation of the contribution of the ionic component to
the structure of Ph4SbX is incorrect.
C(1)
C(43)
C(44)
C(42)
N
C(45)
C(41)
C(35)
C(36)
C(46)
C(34)
C(31)
Sb
C(22)
C(33)
C(32)
C(21)
C(23)
C(11)
C(16)
C(26)
C(12)
C(13)
REFERENCES
C(24)
1. Lebedev, V.A., Bochkova, R.I., Kuz’min, E.A., et al.,
Dokl. Akad. Nauk SSSR, 1981, vol. 260, no. 5, p. 1124.
2. Sharutin, V.V., Sharutina, O.K., Pakusina, A.P., et al.,
Koord. Khim., 2003, vol. 30, no. 2, p. 95.
C(25)
C(15)
C(14)
3. Ferguson, G., Glidewell, C., Lloyd, D., and Metcalfe, S.,
J. Chem. Soc., Perkin Trans., 1988, no. 5, p. 731.
4. Knop, O., Vincent, B.R., and Cameron, T., Can. J.
Chem., 1989, vol. 67, no. 1, p. 63.
Fig. 3. Molecular structure of compound III.
than in complex V (357.2°). The distances Sb–Ceq (av.
2.111 Å) and Sb–Cax (2.154 Å) in II are somewhat sho-
eter than in V (2.119 and 2.165 Å, respectively). The
ratios d(Sb–Cax)/dav(Sb–Ceq) are equal to 1.020 in II and
1.022 in V. The Sb–Cl bond in II (2.732 Å) is longer than
in V (2.686 Å); the elongation of the Sb–Cl bond in II as
compared to the sum of the covalent radii is 13.8%.
Thus, the contribution of the ionic component
[p-Tol4Sb]+Cl– to the structure of II is more essential
than in V. The distortion of a trigonal-bipyramidal coor-
dination of the Sb atom in tetraarylantimony halides is
likely to be influenced by both the nature of the halogen
atom and aryl ligands.
5. Baker, L.-J., Rickard, C.E.F., and Taylor, M.J., J. Chem.
Soc., Dalton Trans., 1995, no. 17, p. 2895.
6. Bordner, J., Anderews, B.C., and Long, G.G., Cryst.
Struct. Commun., 1976, vol. 5, no. 4, p. 801.
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Dokl. Akad. Nauk SSSR, 1983, vol. 268, no. 6, p. 1389.
8. SMART and SAINT-Plus. Versions 5.0. Data Collection
and Processing Software for the SMART System, Bruker
AXS Inc, Madison, WI, USA, 1998.
9. SHELXTL/PC. Versions 5.10. An Integrated System for
Solving, Refining, and Displaying Crystal Structures
from Diffraction Data, Bruker AXS Inc, Madison, WI,
USA, 1998.
Tetraphenylantimony isothiocyanate III has the
structure similar to those of tetraarylantimony chlorides
(Fig. 3). The distortion of a trigonal-bipyramidal con-
figuration of a molecule appears in the values of the
bond angles: the axial NSbC angle is equal to 178.08°,
the average NSbCeq and CaxSbCeq angles are 82.06° and
97.98°, respectively; the sum of angles in equatorial
plane is 354.29° (Table 3). The indicated angles and the
average length of the Sb–Ceq bonds (2.108 Å) and the
Sb–Cax distance (2.139 Å) in III coincide with the anal-
ogous geometric parameters in VII (2.108 Å and
2.140 Å, respectively). The NCS ligand has a linear
geometry, the N–C and C–S distances are equal to
1.115 Å and 1.626 Å, respectively. The analogous dis-
tances in thiocyanic acid are 1.116 Å and 1.561 Å [17].
The Sb–N bond length in III (2.507 Å) is greater than
the sum of the covalent radii of the Sb and N atoms
(1.41 + 0.74 = 2.15 Å [10]). Elongation of the Sb–N
bond in III in comparison with the sum of the covalent
radii is equal to 16.6%.
10. Batsanov, S.S., Zh. Neorg. Khim., 1991, vol. 36, no. 12,
p. 3015.
11. Schomaker, V. and Stevenson, D.S., J. Am. Chem. Soc.,
1941, vol. 63, no. 1, p. 37.
12. Huheey, J.E., Inorganic Chemistry. Principles of Struc-
ture and Reactivity, Cambridge: Harper, 1983.
13. Egorochkin, A.N. and Voronkov, M.G., Elektronnoe
stroenie organicheskikh soedinenii kremniya, germaniya
i olova (Electronic Structure of Organic Compounds of
Silicon, Germanium, and Tin), Novosibirsk: Sib. Otd.
Ross. Akad. Nauk, 2000.
14. Gordon, A.J. and Ford, R.A., A Handbook of Practical
Data, Techniques, and References, New York: Wiley,
1972.
15. Bricklebank, N., Godfrey, S.M., Lane, H.P., et al., J.
Chem. Soc., Dalton Trans., 1994, no. 12, p. 1759.
16. Runsink, J., Swen-Walstra, S.C., and Migchelsen, T.,
Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst.
Chem., 1972, vol. 28B, p. 1331.
17. Smirnov, S.K., Khimicheskaya entsiklopediya (Chemi-
cal Encyclopedia), Moscow: Bol’shaya Rossiiskaya
Entsiklopediya, 1995, vol. 4.
Two remarks should be made about the experimen-
tal data obtained. First, a relationship [3] between the
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 31 No. 2 2005
Sharutin
