Surface reaction of dialkyl phosphite on alumina and magnesia studied by inelastic electron tunneling spectroscopy

Journal Article · Thu Nov 29 04:00:00 EST 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100387a015· OSTI ID:6067462

Higo, Morihide; Kamata, Satsuo ^[1]

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1. Kagoshima Univ. (Japan)

Vibrational spectra of dimethyl, diethyl, and diphenyl phosphite on alumina and magnesia surfaces have been measured by inelastic electron tunneling spectroscopy. These dialkyl phosphites (O,O-dialkyl phosphonates) were adsorbed onto Al{sub 2}O{sub 3} and MgO surfaces from anhydrous benzene solutions by using a spin doping method. The tunneling spectra of phosphorous acid (phosphonic acid) on Al{sub 2}O{sub 3} have also been measured for comparison. Phosphorous acid reacts with surface OH groups of Al{sub 2}O{sub 3} by losing its protons and is adsorbed as phosphite anion (phosphonate dianion) onto the surface. Analysis of the tunneling spectra and comparison of the infrared and Raman spectra of the dialkyl phosphites give information about their molecular structures on Al{sub 2}O{sub 3} and MgO and a surface reaction on them. These dialkyl phosphites decompose by a reaction with the surface OH groups on Al{sub 2}O{sub 3} and MgO to give the adsorbed O-alkyl phosphonate monoanions and phosphonate dianion. The similarity of the tunneling spectra of dimethyl phosphite and that of phosphorous acid suggests that dimethyl phosphite decomposes rapidly to give preferentially the adsorbed phosphonate dianion on the surfaces.

• OSTI ID: 6067462
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:24; ISSN JPCHA; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKALINE EARTH METAL COMPOUNDS
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
DATA
ELECTRON SPECTROSCOPY
ENERGY LEVELS
EXCITED STATES
EXPERIMENTAL DATA
HYDROGEN COMPOUNDS
INFORMATION
INORGANIC ACIDS
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
MEASURING METHODS
MOLECULAR STRUCTURE
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PHOSPHOROUS ACID
SPECTROSCOPY
SURFACE PROPERTIES
VIBRATIONAL STATES