Hydrogen and minor element incorporation in synthetic rutile

AbstractThe solubility and incorporation mechanisms of H and various trivalent and divalent cations in synthetic rutile have been investigated. Experiments performed using different bulk Fe2O3contents demonstrate that Fe3+substitutes onto the main Ti site, charge-balanced by oxygen vacancies. Under more reducing conditions in Fe-poor systems, the concentration of Ti interstitials in rutile is increased, resulting in a decrease in H solubility. Variation in the solubility of different oxides in rutile as a function of ionic radius implies substitution onto the main Ti site, probably charge-balanced by oxygen vacancies. To a lesser degree, substitution of trivalent and divalent cations is locally charge-balanced by H incorporation. Variation in OH-stretching frequencies in infrared spectra as a function of composition implies that octahedral defects and structurally-incorporated H are coupled. However, in all samples, some of the H is also decoupled from substitutional impurities, as is evident from an OH-absorption band at 3279 cm–1. This band corresponds to the main OH band seen in spectra of many natural rutiles, implying that in most rutiles, H defects are decoupled from substitutional defects.

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Remarks to localization of the absorption band of C=S and C=Se stretching vibrations in the infrared spectra of thio- and selenosemicarbazide and of their coordination compounds

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19691353 ◽

1969 ◽

Vol 34 (5) ◽

pp. 1353-1359 ◽

Cited By ~ 3

Author(s):

K. Volka ◽

Z. Holzbecher

Keyword(s):

Absorption Band ◽

Infrared Spectra ◽

Coordination Compounds ◽

Stretching Vibrations

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The intensity of the absorption band in the infrared spectra of magnetized water and sodium oleate solutions

Journal of Applied Spectroscopy ◽

10.1007/bf00608477 ◽

1970 ◽

Vol 13 (4) ◽

pp. 1332-1334

Author(s):

M. A. Orel ◽

I. V. Kagarlitskaya ◽

I. V. Lapatukhin ◽

R. A. Kabirova

Keyword(s):

Absorption Band ◽

Sodium Oleate ◽

Infrared Spectra ◽

Magnetized Water

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Numerical estimation of the peak positions for the 1050-1300cm-1 absorption band due to an ester group in the infrared spectra.

BUNSEKI KAGAKU ◽

10.2116/bunsekikagaku.46.695 ◽

1997 ◽

Vol 46 (9) ◽

pp. 695-702 ◽

Cited By ~ 1

Author(s):

Toshio OGAWA ◽

Kenji HAYASHI ◽

Satoshi OSAWA ◽

Tetsuya KOYAMA

Keyword(s):

Absorption Band ◽

Infrared Spectra ◽

Ester Group ◽

Numerical Estimation

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ADSORPTIVE AND GAS CHROMATOGRAPHIC PROPERTIES OF VARIOUS CATIONIC FORMS OF ZEOLITE X

Canadian Journal of Chemistry ◽

10.1139/v64-342 ◽

1964 ◽

Vol 42 (10) ◽

pp. 2340-2350 ◽

Cited By ~ 74

Author(s):

H. W. Habgood

Keyword(s):

Ionic Radius ◽

Adsorption Process ◽

Divalent Cations ◽

Chromatographic Retention ◽

Monovalent Cations ◽

Zeolite X ◽

Heats Of Adsorption ◽

Quadrupole Interactions ◽

Silver Compound ◽

Retention Volumes

Gas chromatographic retention volumes for O2, N2, CH4, C2H6, C3H8, C4H10, C2H4, and C3H6 have been measured over a range of temperatures between 25 and 400 °C, on columns of the following ion-exchanged forms of zeolite X: Li+, Na+, K+, Mg++, Ca++, Ba++, and Ag+. In addition, for AgX zeolite, full isotherms have been determined for O2, N2, C2H6, and C2H4; and for NaX zeolite, isotherms for C2H6 and C2H4. The gas chromatographic retention volumes agree well with the isotherms in the case of NaX but are significantly low for AgX, presumably as the result of at least a portion of the adsorption process being slow. The heats of adsorption on NaX agree well with literature values for O2, N2, CH4, and C2H6 but are low for C3H8 and C4H10; further indication of slow processes and hence of a limitation of the g.c. technique. The observations can be correlated qualitatively in terms of the interplay of the following effects: (a) cationic field increases with decreasing ionic radius; (b) shielding of smaller cations is greater—at least in the six-membered oxygen-ring sites; (c) divalent cations, while having greater fields, are only half the number of monovalent cations and tend to be found in less exposed sites; and (d) the polarizing power of silver ion, which also occupies all types of exposed sites, is very strong. The most intense interactions were found with AgX; with ethylene a much stronger complex is formed than has been reported for any other silver compound. The significance of molecular quadrupole interactions on these heteroionic surfaces is shown by the much weaker cationic effects observed with O2 (which has negligible quadrupole moment) than with nitrogen.

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ON THE INFRARED ABSORPTION OF WATER AND HEAVY WATER IN CONDENSED STATES

Canadian Journal of Chemistry ◽

10.1139/v56-103 ◽

1956 ◽

Vol 34 (6) ◽

pp. 798-808 ◽

Cited By ~ 88

Author(s):

Paul A. Giguère ◽

K. B. Harvey

Keyword(s):

Thin Films ◽

Absorption Band ◽

Water Molecule ◽

Air Temperature ◽

Heavy Water ◽

Infrared Spectra ◽

Infrared Absorption ◽

Silver Chloride ◽

Strong Absorption Band ◽

Librational Mode

The infrared spectra (from 2 to 30 μ) of thin films of H2O and D2O were measured at various temperatures between 20 ° and −180 °C. A strong absorption band due to the librational mode of the water molecule has its maximum around 710 cm.−1 in the liquid. In ice it is shifted to 800 cm.−1 at −15 °C. and 850 cm.−1 at −170 °C. The corresponding D2O bands show the normal isotope shift. Thin films of water pressed between silver chloride plates could not be crystallized even at liquid air temperature as confirmed by their spectra, which were almost identical with those of the liquid.

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Infrared Spectra of Troponoid Compounds. II. Absorption Band of O–H Stretching Vibration in Some Tropolones

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.34.91 ◽

1961 ◽

Vol 34 (1) ◽

pp. 91-93 ◽

Cited By ~ 12

Author(s):

Yusaku Ikegami

Keyword(s):

Absorption Band ◽

Infrared Spectra ◽

Stretching Vibration

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Correlation between Ionic Radius of Substituting Element and Magnetic Properties of Bi1-xAxFeO3-x/2 (A= Ca, Sr, Pb, Ba) Multiferroics

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.152-153.131 ◽

2009 ◽

Vol 152-153 ◽

pp. 131-134 ◽

Cited By ~ 1

Author(s):

V.A. Khomchenko ◽

Michael Kopcewicz ◽

Armandina M. Lima Lopes ◽

Yuri G. Pogorelov ◽

J.P. Araujo ◽

...

Keyword(s):

Crystal Structure ◽

Magnetic Properties ◽

Spin Structure ◽

Ionic Radius ◽

Oxygen Vacancies ◽

Magnetic State ◽

Weak Ferromagnetism ◽

Host Lattice ◽

A Site ◽

Spiral Spin

Investigation of crystal structure and magnetic properties of the diamagnetically- substituted Bi1-xAxFeO3-x/2 (A= Ca, Sr, Pb, Ba; x= 0.2, 0.3) polycrystalline samples has been carried out. It has been shown that the heterovalent A2+ substitution result in the formation of oxygen vacancies in the host lattice. The solid solutions have been found to possess a rhombohedrally distorted perovskite structure described by the space group R3c. Magnetization measurements have shown that the magnetic state of these compounds is determined by the ionic radius of the substituting elements. A-site substitution with the biggest ionic radius ions has been found to suppress the spiral spin structure of BiFeO3 giving rise to the appearance of weak ferromagnetism.

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The Infrared Spectra of Some 1-(2-Thienyl)-3- and -4-Thiaalkanes

Applied Spectroscopy ◽

10.1366/0003702794925174 ◽

1979 ◽

Vol 33 (6) ◽

pp. 578-581

Author(s):

Norman G. Foster ◽

Bernice B. Bonner ◽

Robert W. Higgins

Keyword(s):

Absorption Band ◽

Infrared Spectra ◽

Thiophene Ring ◽

Absorption Bands ◽

Characteristic Absorption ◽

Molecular Weights ◽

Ring Compounds ◽

Major Absorption Band

The infrared spectra of six 1-(2-thienyl)-3-thiaalkanes and seven 1-(2-thienyl)-4-thiaalkanes (molecular weights from 186 to 270) were obtained for the 4000 to 400 cm−1 range. These spectra are compared with spectra of other thiophene ring compounds substituted in the 2-position for their characteristic absorption bands. The spectra agree with other spectra as to the major absorption band around 680 cm−1 and the 2-substitution overtone pattern. A method of distinguishing between the two groups of compounds from moderate peaks in the 600 to 500 cm−1 (KBr) region is shown. Interference from the 2-alkylthiophenes and the 1-(2-thienyl)-1-thiaalkanes does not occur.

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Effect of functional group conformation on the infrared spectra of some gem difunctional phenylethylene derivatives

Canadian Journal of Chemistry ◽

10.1139/v69-520 ◽

1969 ◽

Vol 47 (17) ◽

pp. 3147-3152 ◽

Cited By ~ 11

Author(s):

D. J. Currie ◽

C. E. Lough ◽

F. K. McClusky ◽

H. L. Holmes

Keyword(s):

Absorption Band ◽

Functional Groups ◽

Infrared Spectra ◽

Functional Group ◽

Plane Deformation ◽

Carbonyl Groups ◽

Deformation Bands ◽

Or Groups ◽

Out Of Plane ◽

Stretching Vibrations

Except for the benzalmalononitriles, two functional group stretching vibrations occur in the infrared (i.r.) spectra of the β,β-difunctional-styrenes with similar functional groups. For geometrically homogeneous compounds with dissimilar functional groups only one absorption band occurs for each functional group. The two bands for similar functional groups have been ascribed to S-cis- and S-trans-conformations of the carbonyl groups with respect to the ethylene and variation in the frequencies of each of these oriented carbonyls to rotation of the functional group or groups out of the plane of the ethylene by steric factors.Frequencies for ethylenic C—H out of plane deformation bands for β-monofunctional styrenes accorded with those already assigned to this vibration. A similar assignment could not be made for the difunctional analogues.

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