The title compound, Rh-2(O2CCF3)(4), without any exogenous axial ligan
ds, has been obtained in crystalline form by sublimation. Its crystal
structure has been determined: space group P ($) over bar 1 with a = 5
.2499(5), b = 8.491 (2), c = 9.172(2) Angstrom, alpha = 88.80(2), beta
= 88.53(1), gamma = 76.43(1)degrees, V = 397.3(1) Angstrom 3, Z = 1.
The molecules are linked by axially ligating each other to form infini
te chains. The Rh-Rh distance is 2.3813(8) Angstrom. The volatility of
Rh-2(O2CCF3)(4) should allow spectroscopic study of the isolated mole
cules and therefore the electronic structure has been treated by the S
CF-X alpha-SW method. The level ordering and composition show signific
ant differences from those of Rh,(O,CH)4, although in both molecules t
here is a strong Rh-Rh sigma bond. Ionization potentials have been est
imated by the transition state method.