Mononuclear rhenium carbonyls on MgO: Characterization of the metal-support interface by extended x-ray absorption fine structure spectroscopy

Journal Article · Thu Nov 28 00:00:00 EST 1991 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100177a062· OSTI ID:6924180

Chang, J R; Gron, L U; Honji, A; Sanchez, K M; Gates, B C ^[1]

---

1. Univ. of Delaware, Newark (United States)

Structures formed on the surface of fully dehydroxylated MgO by adsorption of [HRe(CO)[sub 5]] were characterized by extended x-ray absorption fine structure (EXAFS) spectroscopy. The rhenium carbonyl initially was molecularly adsorbed, interacting with the MgO surface as the proton was partially removed by a basic oxygen of the surface; the average Re-C and Re-O* coordination numbers (where O* refers to the carbonyl oxygen) are about 5. There is no EXAFS evidence for interactions of carbonyl oxygen with the surface. The average Re-C and Re-O* distances are 1.94 and 3.13 [angstrom], respectively. When the adsorbed [HRe(CO)[sub 6]] was heated to 80C in hydrogen, it lost two CO ligands per Re and formed a sub-carbonyl formulated as [Re(CO)[sub 3][OMg][HOMg][sub 2]], where the brackets refer to groups terminating the bulk MgO. The average Re-C, Re-O*, and Re-O distances are 1.91, 3.12, and 2.13 [angstrom], respectively. The Re-O distance is equal, within [plus minus] 0.1 [angstrom], to the metal-oxygen distances in the only other well-characterized metal sub-carbonyls on metal oxides and to the metal-oxygen distances in numerous organometallic complexes with oxygen-containing ligands.

• DOE Contract Number: FG02-87ER13790; AC02-76CH00016
• OSTI ID: 6924180
• Journal Information: Journal of Physical Chemistry; (United States), Vol. 95:24; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CARBONYLS
CHEMISORPTION
MAGNESIUM OXIDES
SORPTIVE PROPERTIES
RHENIUM COMPOUNDS
RHENIUM HYDRIDES
ABSORPTION SPECTROSCOPY
BOND LENGTHS
EXPERIMENTAL DATA
FINE STRUCTURE
MOLECULAR STRUCTURE
ORGANOMETALLIC COMPOUNDS
SUPPORTS
X-RAY SPECTROSCOPY
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
DATA
DIMENSIONS
HYDRIDES
HYDROGEN COMPOUNDS
INFORMATION
LENGTH
MAGNESIUM COMPOUNDS
MECHANICAL STRUCTURES
NUMERICAL DATA
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REFRACTORY METAL COMPOUNDS
SEPARATION PROCESSES
SORPTION
SPECTROSCOPY
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS
400201* - Chemical & Physicochemical Properties