Syntheses and Structures of F 6 XeNCCH 3 and F 6 Xe(NCCH 3 ) 2

Acetonitrile and the potent oxidative fluorinating agent XeF 6 react at −40 °C in Freon‐114 to form the highly energetic, shock‐sensitive compounds F 6 XeNCCH 3 ( 1 ) and F 6 Xe(NCCH 3 ) 2 ⋅CH 3 CN ( 2 ⋅CH 3 CN). Their low‐temperature single‐crystal X‐ray structures show that the adducted XeF 6 molecules of these compounds are the most isolated XeF 6 moieties thus far encountered in the solid state and also provide the first examples of Xe VI N bonds. The geometry of the XeF 6 moiety in 1 is nearly identical to the calculated distorted octahedral ( C 3 v ) geometry of gas‐phase XeF 6 . The C 2 v geometry of the XeF 6 moiety in 2 resembles the transition state proposed to account for the fluxionality of gas‐phase XeF 6 . The energy‐minimized gas‐phase geometries and vibrational frequencies were calculated for 1 and 2 , and their respective binding energies with CH 3 CN were determined. The Raman spectra of 1 and 2 ⋅CH 3 CN were assigned by comparison with their calculated vibrational frequencies and intensities.