N. Bricklebank et al., SOIL-STATE STRUCTURES OF TRIARYLANTIMONY DIHALIDES - THE ISOLATION OFSOME MIXED-HALIDE SPECIES AND CRYSTAL-STRUCTURES OF PH3SBL2 AND [PH4SB]L3, Journal of the Chemical Society. Dalton transactions, (12), 1994, pp. 1759-1763
Fifteen compounds of stoichiometry R3SbX2 (R = Ph or substituted aryl;
X2 = Br2, I2 or IBr) were synthesised and studied by Raman spectrosco
py. The crystal structure of Ph3Sbl2 has been determined, which shows
it to be a distorted trigonal-bipyramidal molecule. The distortion fro
m regular trigonalbipyramidal geometry may be explained by a pseudorot
ation process towards a rectangular pyramid. Moreover, there are two i
ndependent molecules within the unit cell and its distoned structure i
s in direct contrast to the known Ph3SbX2 (X = Cl or Br) which both ad
opt regular trigonal-bipyramidal geometry. The interhalogen compounds
R3SbIBr also have trigonal-bipyramidal geometry. In direct contrast to
the molecules Ph3EI2 (E = P or As), which ionise in solution to form
[Ph3EI]I, Ph3SbI2 is chemically changed in acetonitrile solution and f
orms the ionic [Ph4Sb]I3, there being no evidence for [Ph3Sbl]I. The c
rystal structure of [Ph4Sb]I3 has also been determined.