THE MOLECULAR-STRUCTURE OF TRIMETHYLTANTALUM DICHLORIDE, (CH3)(3)TACL2, AS DETERMINED BY GAS ELECTRON-DIFFRACTION

The gas electron diffraction data of (CH3)(3)TaCl2, recorded with a no zzle temperature of about 25 degrees C, show that the coordination geo metry of the metal atom is trigonal bipyramidal with the Cl atoms in a xial positions. Least-squares refinements based on a molecular model ( hydrogen atoms excluded) of D-3h symmetry yield the bond distances (r( a)) Ta-C = 215.8(5) pm and Ta-Cl = 231.7(3) pm.