Infrared spectroscopic studies of solvent effects on the conformation of n-alkanes

1986 ◽  
Vol 64 (8) ◽  
pp. 1544-1547 ◽  
Author(s):  
H. L. Casal ◽  
P. W. Yang ◽  
H. H. Mantsch
Keyword(s):  
Chain Length ◽  
Infrared Spectra ◽  
Solvent Effects ◽  
Spectroscopic Studies ◽  
Thermodynamic Quantities ◽  
Branched Hydrocarbons ◽  
Infrared Spectroscopic ◽  
Induced Changes

The infrared spectra of specifically deuterated n-tridecane-7,7-d2 pure and mixed with several linear and branched hydrocarbons have been measured as a function of temperature. The average gauche fraction at the middle of the n-tridecane chain has been determined from the intensities of conformation-specific CD2 rocking bands. The results indicate that the concentration of gauche rotamers in the centre of the n-C13 chains varies with the solvent. For example, when n-tridecane is dissolved in other n-hydrocarbons the gauche concentration decreases when the chain length of the solvent is shorter than n-C13 and increases when the solvent chains are longer than n-C13. However, no simple, direct correlation is found between these solvent-induced changes in gauche concentration and measured thermodynamic quantities of mixing.

Infrared spectroscopic studies of melt-deposited salt occlusion by zeolites

1980 ◽  
Vol 33 (3) ◽  
pp. 659 ◽  
Author(s):  
AT Petfield ◽  
RP Cooney
Keyword(s):  
Cation Exchange ◽  
Infrared Spectra ◽  
Sodium Nitrate ◽  
Internal Surface ◽  
Spectroscopic Studies ◽  
Lattice Mode ◽  
Infrared Spectroscopic

Sodium nitrate is occluded by the zeolites NaX and NaA. In addition to occluded nitrate, adherent nitrate appears to contribute to the infrared spectra of most zeolite+NaNO3 systems. A lattice mode has been detected for the system NaA+NaNO3, which is interpreted in terms of an ordered occluded phase. Evidence indicates that both occlusion and cation exchange occur in the system NaA+LiNO3. The extent of occlusion of NaNO3 by NaX is much less than by NaA. Interaction between the zeolitic cation and the occluded phase is not significant even when the zeolitic cation is strongly coordinating (e.g. Zn2+). Little, if any, KSCN is occluded by zeolites NaA and NaX, and KSCN appears to react on the internal surface of ZnX.

SPECTROSCOPIC STUDIES OF KETO–ENOL EQUILIBRIA: PART 1. SOLVENT EFFECTS

1962 ◽  
Vol 40 (12) ◽  
pp. 2267-2271 ◽  
Author(s):  
A. S. N. Murthy ◽  
A. Balasubramanian ◽  
C. N. R. Rao ◽  
T. R. Kasturi
Keyword(s):  
Infrared Spectra ◽  
Solvent Effects ◽  
Ethyl Acetoacetate ◽  
Spectroscopic Studies ◽  
Ultraviolet Spectroscopy ◽  
Keto Form ◽  
Local Association ◽  
Characteristic Frequencies ◽  
Solvent Molecules

Solvent effects on the keto–enol equilibria of ethyl acetoacetate, acetylacetone, ethyl cyclopentanone-2-carboxylate, and methyl 4-methylcyclopentane-1-,2-dione-3,4,5-tricarboxylate have been studied by ultraviolet spectroscopy. The extent of enolization is mainly determined by the stabilization of the keto form by local association with polar or proton-donating solvent molecules, just as in the case of n → π* transitions and infrared stretching frequencies. Solvent effects on infrared spectra reveal useful information regarding the characteristic frequencies of the tautomers.

Infrared spectroscopic studies of wind-tunnel contamination

1998 ◽  
Author(s):  
A. Walker ◽  
D. Plusquellic ◽  
G. Fraser ◽  
A. Weber ◽  
W. Lafferty
Keyword(s):  
Wind Tunnel ◽  
Spectroscopic Studies ◽  
Infrared Spectroscopic

Infrared spectroscopic study of the YPO4-YCrO4 system

1985 ◽  
Vol 50 (10) ◽  
pp. 2139-2145
Author(s):  
Alexander Muck ◽  
Eva Šantavá ◽  
Bohumil Hájek
Keyword(s):  
Spectroscopic Study ◽  
Infrared Spectra ◽  
Point Of View ◽  
Mixed Crystals ◽  
Crystal Symmetry ◽  
Infrared Spectroscopic Study ◽  
X Ray Diffraction ◽  
X Ray ◽  
Infrared Spectroscopic ◽  
Diffraction Patterns

The infrared spectra and powder X-ray diffraction patterns of polycrystalline YPO4-YCrO4 samples are studied from the point of view of their crystal symmetry. Mixed crystals of the D4h19 symmetry are formed over the region of 0-30 mol.% YPO4 in YCrO4. The Td → D2d → D2 or C2v(GS eff) correlation is appropriate for both PO43- and CrO43- anions.

Sign in / Sign up

Export Citation Format

Share Document