Calculation of correlation times for the. gamma. -alumina-supported molybdenum subcarbonyl, Mo(CO) sub 3 (ads)

Journal Article · Wed Jul 05 04:00:00 EDT 1989 · Journal of the American Chemical Society; (USA)

DOI:https://doi.org/10.1021/ja00196a012· OSTI ID:7070052

Wagner, G W; Hanson, B E ^[1]

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1. Virginia Polytechnic Institute and State Univ., Blacksburg (USA)

The theory of carbon-13 NMR line widths in the solid state for molecules with large chemical shift anisotropies is applied to the adsorbed molybdenum subcarbonyls Mo(CO){sub 3}(ads) and Mo(CO){sub 5}(ads). Correlation times for the rotation of the molybdenum subcarbonyl groups Mo(CO){sub 3}(ads) and Mo(CO){sub 5}(ads) on partially dehydroxylated alumina are calculated. Good agreement is obtained between data reported at observation frequencies of 15 to 75.5 MHz for carbon-13 for Mo(CO){sub 3}(ads). The correlation time for this adsorbed species is calculated to have a lower limit of 4.6 {plus minus} 0.5 ms. The presence of broad lines in the room temperature spectra for Mo(CO){sub 3}(ads) is thus explained by a slow molecular motion. Data for Mo(CO){sub 5}(ads) are available at observation frequencies of 15 to 90.5 MHz. A good fit to the experimental data is obtained assuming either long or short correlation times for this species. Thus literature estimates of <10{sup {minus}6}s for the correlation time for this species cannot be confirmed with certainty from the analysis presented here.

• OSTI ID: 7070052
• Journal Information: Journal of the American Chemical Society; (USA), Journal Name: Journal of the American Chemical Society; (USA) Vol. 111:14; ISSN 0002-7863; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104 -- Metals &amp; Alloys-- Physical Properties
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400200* -- Inorganic
Organic
&amp; Physical Chemistry
ALUMINATES
ALUMINIUM COMPOUNDS
CALCULATION METHODS
CARBONYLS
COMPLEXES
CORRELATION FUNCTIONS
DATA ANALYSIS
FUNCTIONS
MOLYBDENUM COMPLEXES
NMR SPECTRA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
OXYGEN COMPOUNDS
SPECTRA
TRANSITION ELEMENT COMPLEXES