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Showing papers in "Inorganic Chemistry in 1974"



Journal Article•DOI•
TL;DR: In this article, the infrared spectra of powdered strontium and barium hydroxyapatites and their deuterated analogs were reported at 48 and 185 deg in the 4000-200cm-/sup 1/ region.
Abstract: The infrared spectra of powdered calcium hydroxyapatite isotopically substituted with D, /sup 18/O, /sup 44/Ca, and /sup 48/Ca and infrared spectra of powdered strontium and barium hydroxyapatites and their deuterated analogs are reported at 48 and - 185 deg in the 4000-200cm-/sup 1/ region. Band assignments, based on isotopic frequency shifts, band intensity, band temperature dependency, and comparisons between corresponding bands of these structurally related apatites are presented for the above and other apatites. (auth)

604 citations



Journal Article•DOI•
TL;DR: In this article, the effects of low temperature and differences in physical properties of the apatites on the infrared vibrational frequencies are discussed, with particular emphasis on purity, stoichiometry, crystal perfection, and gravimetrically monitoring apatite composition.
Abstract: Procedures are described for preparation of calcium, strontium, and barium hydroxyapatites, their deuterated analogs, and calcium hydroxyapatite enriched with isotopic calcium with particular emphasis on purity, stoichiometry, crystal perfection, and gravimetrically monitoring the apatite composition. The effects of low temperature and differences in physical properties of the apatites on the infrared vibrational frequencies are discussed. Shifts in the internal phosphate modes to higher frequencies, in the barium-strontium--calcium hydroxyapatite sequence and also on cooling, are attributed primarily to increased interphosphate repulsion concomitant with lattice contraction. Causes for variation in the frequencies and intensities of the OH modes are considered from several viewpoints including the presence of weak OH-O bonding which is neither conclusively established nor rejected. Finally, marked increases in OH band intensities in the barium--strontium--calcium hydroxyapatite sequence are attributed to differences in OH bonding rather than to other effects.

187 citations















Journal Article•DOI•
TL;DR: In this article, the Strukturen der aus den entsprechenden Metallcarbonylen und Bortrihalogeniden oder AlBr3 gebildeten Addukte (I)-(VII) werden anhand von IR-Spektren speziell anhand der CO-Bindungsfrequenzen diskutiert.
Abstract: Die Strukturen der aus den entsprechenden Metallcarbonylen und Bortrihalogeniden oder AlBr3 gebildeten Addukte (I)-(VII) werden anhand von IR-Spektren speziell anhand der CO-Bindungsfrequenzen diskutiert.





Journal Article•DOI•
TL;DR: In this article, the core electron binding energies for analogous compounds of carbon, silicon, and germanium have been measured by X-ray photoelectron spectroscopy in the gas phase.
Abstract: Core electron binding energies for analogous compounds of carbon, silicon, and germanium have been measured by X-ray photoelectron spectroscopy in the gas phase. The chemical shifts have been correlated by the electrostatic potential equation using charge distributions from extended Huckel theory, CNDO/2, and an electronegativity equalization method. The data can be rationalized without any consideration p..pi -->..d..pi.. or p(pi)..-->..d(pi) in the silicon and germanium compounds.