Determination of the concentration of surface hydroxyl groups on silicon dioxide particles by the method of IR spectroscopy

1982 ◽  
Vol 36 (3) ◽  
pp. 328-332 ◽  
Author(s):  
B. Z. Gorbunov ◽  
A. S. Safatov
Keyword(s):  
Ir Spectroscopy ◽  
Silicon Dioxide ◽  
Hydroxyl Groups ◽  
Surface Hydroxyl ◽  
Surface Hydroxyl Groups

Adsorption von Aceton an Magnesiumoxid.

1976 ◽  
Vol 31 (7) ◽  
pp. 922-928 ◽  
Author(s):  
Franz Koubowetz ◽  
Heinrich Noller ◽  
Johannes Latzel
Keyword(s):  
Ir Spectroscopy ◽  
Hydrogen Bonds ◽  
Mass Spectrometer ◽  
Heat Of Adsorption ◽  
Hydroxyl Groups ◽  
Surface Hydroxyl ◽  
Carbonyl Band ◽  
Surface Hydroxyl Groups ◽  
Weak Hydrogen Bonds

The adsorption of acetone on MgO was studied by IR spectroscopy, the desorption products were analyzed with a mass spectrometer. Furthermore, the heat of adsorption and the coverage of the surface were calculated from adsorption isothermes measured at various temperatures.Acetone is adsorbed over (weak) hydrogen bonds to surface hydroxyl groups as well as coordinatively bound to the cation Mg2+. This bonding to the cations causes strong shifts of the carbonyl band (up to 100 cm-1) and the CH3 bands (Δν≈55 cm-1) to lower wavenumbers. At 120°C, desorption of acetone, and at 320°C and 400°C of methane is detected. Using d6-acetone or D2O, the methane observed can be shown to be formed from hydrogen of acetone rather than with participation of hydrogen of surface hydroxyl groups.

The synthesis and structure of silica-supported bis(h5-cyclopentadienyl)dichlorotitanium(IV) complexes

1986 ◽  
Vol 51 (7) ◽  
pp. 1430-1438 ◽  
Author(s):  
Alena Reissová ◽  
Zdeněk Bastl ◽  
Martin Čapka
Keyword(s):  
Free Surface ◽  
Hydroxyl Groups ◽  
Titanium Complex ◽  
Surface Hydroxyl ◽  
Surface Hydroxyl Groups ◽  
Free Hydroxyl ◽  
Cyclopentadienyl Anion

The title complexes have been obtained by functionalization of silica with cyclopentadienylsilanes of the type Rx(CH3)3 - xSi(CH2)nC5H5 (x = 1-3, n = 0, 1, 3), trimethylsilylation of free surface hydroxyl groups, transformation of the bonded cyclopentadienyl group to the cyclopentadienyl anion, followed by coordination of (h5-cyclopentadienyl)trichlorotitanium. The effects of single steps of the above immobilization on texture of the support, the number of free hydroxyl groups, the coverage of the surface by cyclopentadienyl groups and the degree of their utilization in anchoring the titanium complex have been investigated. ESCA study has shown that the above anchoring leads to formation of the silica-supported bis(h5-cyclopentadienyl)dichlorotitanium(IV) complex.

Sign in / Sign up

Export Citation Format

Share Document