Mass spectrometric study of high-temperature dehydroxylation of disperse silicas and the interpretation of their IR spectra in the region of Si-O stretching vibrations (in Russian)
Journal Article
·
· Theor. Exp. Chem. (Engl. Transl.); (United States)
Field-desorption mass spectrometry has been used to determine the lower boundary of the temperature interval for the removal of surface hydroxyl groups of aerosil. Both in the regime of cation desorption and in the regime of anion desorption, at temperatures above 900/sup 0/K, OH ions of the corresponding sign are registered. It is concluded that the thermal decomposition of the surface bonds triple bond Si-OH is homolytic in character. A mechanism is proposed for the dehydroxylation of SiO/sub 2/, according to which the initially formed radical centers triple bond Si and triple bond SiO change into ions: triple bond Si/sup +/ (I) and triple bond SiO/sup -/ (II). The bands at 888 and 908 cm/sup -1/ in the IR spectra of silicas obtained at high temperatures are assigned to vibrations of Si-O bonds in I and II, respectively.
- Research Organization:
- L. V. Pisarzhevskii Institute of Physical Chemistry, Kiev, USSR
- OSTI ID:
- 6090437
- Journal Information:
- Theor. Exp. Chem. (Engl. Transl.); (United States), Journal Name: Theor. Exp. Chem. (Engl. Transl.); (United States) Vol. 21:1; ISSN TEXCA
- Country of Publication:
- United States
- Language:
- Russian
Similar Records
Modeling tetrahedral edge shared defect sites on dehydroxylated silica: A molecular orbital study
Active sites on SiO{sub 2}. Role in CH{sub 3}OH decomposition
Quantum-chemical investigation of mechanism of dehydroxylation of crystalline and amorphous aluminosilicates
Conference
·
Tue Dec 30 23:00:00 EST 1997
·
OSTI ID:567883
Active sites on SiO{sub 2}. Role in CH{sub 3}OH decomposition
Journal Article
·
Sat Jul 01 00:00:00 EDT 1995
· Langmuir
·
OSTI ID:91253
Quantum-chemical investigation of mechanism of dehydroxylation of crystalline and amorphous aluminosilicates
Journal Article
·
Tue Jul 01 00:00:00 EDT 1986
· Kinet. Catal. (Engl. Transl.); (United States)
·
OSTI ID:7005316
Related Subjects
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
640304 -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ANIONS
CATALYSTS
CATALYTIC EFFECTS
CATIONS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL BONDS
CHEMICAL REACTIONS
DECOMPOSITION
ELECTRON SPIN RESONANCE
ELECTRONIC STRUCTURE
EMISSION
ENERGY LEVELS
EVEN-EVEN NUCLEI
EXCITED STATES
FIELD EMISSION
HYDROGEN COMPOUNDS
HYDROXIDES
INFRARED SPECTRA
IONIZATION
IONIZATION POTENTIAL
IONS
ISOTOPE EFFECTS
ISOTOPES
ISOTOPIC EXCHANGE
LIGHT NUCLEI
MAGNETIC RESONANCE
MASS SPECTRA
MINERALS
NUCLEI
OXIDE MINERALS
OXIDES
OXYGEN 16
OXYGEN 18
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PYROLYSIS
RESONANCE
SILICA
SILICON COMPOUNDS
SILICON OXIDES
SPECTRA
STABLE ISOTOPES
THERMOCHEMICAL PROCESSES
VIBRATIONAL STATES
400201* -- Chemical & Physicochemical Properties
640304 -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ANIONS
CATALYSTS
CATALYTIC EFFECTS
CATIONS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL BONDS
CHEMICAL REACTIONS
DECOMPOSITION
ELECTRON SPIN RESONANCE
ELECTRONIC STRUCTURE
EMISSION
ENERGY LEVELS
EVEN-EVEN NUCLEI
EXCITED STATES
FIELD EMISSION
HYDROGEN COMPOUNDS
HYDROXIDES
INFRARED SPECTRA
IONIZATION
IONIZATION POTENTIAL
IONS
ISOTOPE EFFECTS
ISOTOPES
ISOTOPIC EXCHANGE
LIGHT NUCLEI
MAGNETIC RESONANCE
MASS SPECTRA
MINERALS
NUCLEI
OXIDE MINERALS
OXIDES
OXYGEN 16
OXYGEN 18
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PYROLYSIS
RESONANCE
SILICA
SILICON COMPOUNDS
SILICON OXIDES
SPECTRA
STABLE ISOTOPES
THERMOCHEMICAL PROCESSES
VIBRATIONAL STATES