The molecular structures of the MoF4 and MoF5 molecules have been investiga
ted by synchronous gas phase electron diffraction/mass spectrometry. The eq
uilibrium structure of MoF4 is tetrahedral. The molecule MoF5 has C-2 nu sy
mmetry due to the Jahn-Teller effect. Intrinsic periodicity of the M-X bond
distance in the MX4 halides along the series of d-elements is discussed. (
C) 2001 Elsevier Science B.V. All rights reserved.