Rotational Spectra of Argon Acetone: A Two-Top Internally Rotating Complex

✍ Scribed by Lu Kang; Alison R. Keimowitz; Michaeleen R. Munrow; Stewart E. Novick

• Book ID: 102604939
• Publisher: Elsevier Science
• Year: 2002
• Tongue: English
• Weight: 237 KB
• Volume: 213
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.2002.8551

✦ Synopsis

The rotational spectra of the argon acetone weakly bound complex was studied by pulsed jet Fabry-Perot Fourier transform microwave spectroscopy. Over 500 transitions of the complex were measured between 5.5 and 26 GHz from J = 2-1 to J = 12-11. The two methyl groups undergo hindered internal rotation resulting in four or five internal rotation states. The microwave transitions are within these states, resulting in a splitting of each rotational transition into four and sometimes five distinct transitions. The three-fold barrier to internal rotation is determined to be 260 cm -1 , 2% less than the 266 cm -1 barrier in acetone itself. The structure of the complex has the argon atom above the heavy atom plane of the acetone, 3.52 A ❛ from the C= =O bond and approximately in the C s plane, which is perpendicular to the C-C-C plane of acetone.