Showing papers on "Infrared spectroscopy published in 1971"
Book•
01 Jan 1971
TL;DR: In this article, the authors present an overview of the main components of optical atomic spectrometers and their application in the field of surface characterization by Spectroscopy and Microscopy.
Abstract: Introduction. Section I: Measurement Basics. Electrical Components and Circuits. Operational Amplifiers in Chemical Instrumentation. Digital Electronics and Microcomputers. Signals and Noise. Section II: Atomic Spectroscopy. An Introduction to Spectrometric Methods. Components of Optical Instruments. An Introduction to Optical Atomic Spectrometry. Atomic Absorption and Atomic Fluorescence Spectrometry. Atomic Emission Spectrometry. Atomic Mass Spectrometry. Atomic X-Ray Spectrometry. Section III: Molecular Spectroscopy. An Introduction to Ultraviolet/Visible Molecular Absorption Spectrometry. Applications of Ultraviolet/Visible Molecular Absorption Spectrometry. Molecular Luminescence Spectrometry. An Introduction to Infrared Spectrometry Applications of Infrared Spectrometry. Raman Spectroscopy. Nuclear Magnetic Resonance Spectroscopy. Molecular Mass Spectrometry. Surface Characterisation by Spectroscopy and Microscopy. Section IV: Electroanalytical Chemistry. Introduction to Electroanalytical Chemistry. Potentiometry. Coulometry. Voltammetry. Section V: Separation Methods. An Introduction to Chromatographic Separations. Gas Chromatography. High-Performance Liquid Chromatography. Supercritical Fluid Chromatography and Extraction. Capillary Electrophoresis and Capillary Electrochromatography. Section VI: Miscellaneous Methods. Thermal Methods. Radiochemical Methods. Automated Methods of Analysis. Appendices.
3,325 citations
01 Jan 1971
TL;DR: In this article, the experimental, theoretical, and empirical correlations between functional organic groups and the infrared spectrum were discussed and many examples of spectra of inorganic compounds in the solid phase were presented.
Abstract: This chapter discusses the experimental, theoretical, and empirical correlations between functional organic groups and the infrared spectrum. The application of infrared spectroscopy to the identification of inorganic compounds is less successful. In obtaining infrared spectra of inorganic solids, an experimental complication arises from possible chemical reaction between the inorganic compound and the infrared window material or support medium. The chapter presents many examples of spectra of inorganic compounds in the solid phase. The majority of these compounds are crystalline solids in which the crystallographic unit cell contains several polyatomic ions or molecules. Optical modes called lattice modes of vibration result from the motion of one polyatomic group relative to another within the unit cell. Lattice modes occur in the region 400–10 cm −1 and are characteristic of specific crystal geometry. They are used as fingerprints for an inorganic compound in much the same way as the internal modes of vibration of organic compounds are used in the region 4000–400 cm −1 .
1,578 citations
TL;DR: In this paper, the infrared spectra of poly(acetylene), poly(d2), copoly(acety+acetylene-d2) and copoly (acetylene+acetane-d1+acetene-d 2) are reported over a wide temperature range (ca. −100 to 180°C) and a tentative assignment of the observed spectra is made on the basis of model structures in which infinite planar chains of all trans, all trans-cisoid, and all cis-transoid configurations are assumed.
Abstract: The infrared spectra of poly(acetylene), poly(acetylene-d2), copoly(acety+acetylene-d2), and copoly(acetylene+acetylene-d1+acetylene-d2) prepared by the Ti(OC4H9)4–Al(C2H5)3 system over a wide temperature range (ca. −100 to 180°C) are reported. A tentative assignment of the observed spectra is made on the basis of model structures in which infinite planar chains of all trans, all trans–cisoid, and all cis–transoid configurations are assumed. The spectral data are best interpreted on the basis of an all cis-transoid (or an all trans-cisoid) structure for the polymers prepared at temperatures lower than −78°C, and an all trans structure for the polymers prepared at temperatures higher than 150°C.Simplified calculations of the C-H and C-D out-of-plane deformation frequencies are made for various model chains. It has been concluded from a comparison of the observed and calculated frequencies that the cis-opening of the triple bond occurs in a polymerization reaction with the Ti(OC4H9)4–Al(C2H5)3 catalyst system at low temperatures.
550 citations
531 citations
522 citations
TL;DR: In this article, a new technique was presented for obtaining the absorption spectra of small samples and low concentrations of gases, which makes use of currently available sources of wavelength-tunable intense coherent light such as the optical parametric oscillator, dye laser, or tunable diode laser.
Abstract: A new technique is presented for obtaining the absorption spectra of small samples and low concentrations of gases. The technique makes use of currently available sources of wavelength‐tunable intense coherent light such as the optical parametric oscillator, dye laser, or tunable diode laser. The absorbed power is detected by the heating and resultant pressure rise in the absorbing gas. An initial experiment with a 15‐mW He–Ne laser operating at 3.39 μ has shown a sensitivity adequate to measure the absorption of a concentration of 10−8 of methane in nitrogen. It is expected that, with higher‐power sources of tunable ir radiation, it may be possible in the future to detect concentrations of impurities as low as 10−13.
498 citations
TL;DR: In this article, the infrared and Raman frequencies of monoclinic zirconia and stabilized and metastable tetragonal and cubic cubic Zirconias were established, and the effects of heating, grinding and adding stabilizing oxides on the ir spectra were determined.
Abstract: The infrared and Raman frequencies of monoclinic zirconia and of stabilized and metastable tetragonal and cubic zirconias were established. Infrared spectra were examined by the powder transmission (CsI pellet) and surface reflection techniques. The effects of heating, grinding, and adding stabilizing oxides on the ir spectra were determined. The spectra develop additional bands as the crystal symmetry is lowered, and certain of these bands are highly sensitive to strain-induced distortions of the crystal lattice. Practical applications of ir and Raman spectroscopy to zirconia technology are discussed.
420 citations
TL;DR: In this article, the elastic constants and the dispersion curves for phonons propagating along (0,0, xi ) and ( xi, xi, 0) are calculated using a rigid ion model with short range central axially symmetric forces and long range Coulomb forces which gives satisfactory agreement with the experimentally observed frequencies.
Abstract: For Pt. II see abstr. A71824 of 1970. The polarized infrared reflection absorption and laser Raman spectra have been recorded at both 300K and 100K for single crystals of SnO2. The dielectric parameters epsilon ' and epsilon " have been derived and the optically active transverse and longitudinal k=0 phonon frequencies found. The elastic constants and the dispersion curves for phonons propagating along (0,0, xi ) and ( xi , xi ,0) are calculated using a rigid ion model with short range central axially symmetric forces and long range Coulomb forces which gives satisfactory agreement with the experimentally observed frequencies. The principal force constants and the effective charges on the ions are compared with those for other crystals with the rutile structure. The multiphonon infrared absorption is compared with theoretical predictions based on selection rules and the calculated phonon dispersion curves. The hydroxyl ion impurities are shown to be oriented parallel to the crystal's optic axis.
226 citations
TL;DR: In this article, a computer program based on a procedure discussed by Powell has been developed for the resolution of overlapping peaks in data output from x-ray diffraction, ion-exchange chromatography with spectroscopic detection, and infrared spectroscopy.
Abstract: A computer program based on a procedure discussed by Powell has been developed for the resolution of overlapping peaks in data output from x-ray diffraction, ion-exchange chromatography with spectroscopic detection, and infrared spectroscopy. A polynomial background is also fitted to the data so that recourse to arbitrary graphical methods for separating peaks and background is no longer necessary.
175 citations
TL;DR: The melting point, solubility and infrared spectra of a number of aromatic imides, mainly disubstituted N.N′-diphenylpyromellitimides, have been determined as mentioned in this paper.
Abstract: The melting point, solubility and infrared spectra of a number of aromatic imides, mainly disubstituted N.N′-diphenylpyromellitimides, have been determined. The variation in properties observed could be explained satisfactorily by making certain assumptions about the planarity, polarisation and intermolecular interactions of the compounds.
Schmelzpunkt, Loslichkeit und Infrarot-Spektren mehrerer aromatischer Imide, hauptsachlich zweifach substituierter N.N′-Diphenylpyromellitimide, wurden gemessen. Die Verschiedenartigkeit der beobachteten Eigenschaften in Abhangigkeit von der Struktur konnte durch gewisse Annahmen uber Planaritat, Polarisierung und intermolekulare Wechselwirkungen befriedigend erklart werden.
170 citations
TL;DR: In this paper, the infrared spectra of α-glucose and three C-deuterated d -glucoses in water and deuterium oxide were compared.
TL;DR: In this paper, the authors show that half of the implanted atoms are incorporated into microregions of SiC which are surrounded by bulk silicon, and that SiC is observed to form at temperatures ≈ 850°C.
Abstract: The production of SiC in single‐crystal silicon by C12+ implantation to fluences of 1017/cm2‐side followed by annealing has been detected by the characteristic infrared absorption of the TO phonon of SiC. Immediately following room‐temperature implantation and after 20‐min isochronal anneals up to temperatures ≤ 825°C, a previously unreported broad absorption band centered at 700–725 cm−1 is observed. SiC is observed to form at temperatures ≈ 850°C. For anneals ≥ 850°C, most of the broad absorption band shifts into the SiC‐TO phonon absorption band. From the infrared absorption measurements together with the results of He+ backscattering, we conclude that about half of the implanted atoms are incorporated into microregions of SiC which are surrounded by bulk silicon.
TL;DR: In this paper, a study has been made of the infrared O-H bands for CH3OH, DOH, and H2O in solution and of their correlation with hydrogen bonding and solvent basicity.
Abstract: A study has been made of the infrared O—H bands for CH3OH, DOH, and H2O in solution and of their correlation with hydrogen bonding and solvent basicity. Infrared bands for the three fundamentals an...
TL;DR: In this paper, the role of the catalyst is primarily to bring the reactants together in suitable orientation, and the four catalysts, which show a wide range of acidity and are all active for the Claus reaction (2H 2 S + SO 2 → 3S + 2H 2 O), were γ-alumina (the main constituent of commercial bauxite catalysts), doped with NaOH, sodium Y zeolite, and hydrogen Y Zeolite.
TL;DR: In this paper, the atomic beams of potassium and rubidium with oxygen molecules at high dilution in argon together on a salt window at 15°K produces the KO2 and RbO2 molecules, as identified by infrared spectra.
Abstract: Deposition of atomic beams of potassium and rubidium with oxygen molecules at high dilution in argon together on a salt window at 15°K produces the KO2 and RbO2 molecules, as identified by infrared spectra. Secondary reaction yields the KO2K and RbO2Rb molecules. Oxygen isotopic mixtures and simultaneous deposition of two different alkali‐metal atoms verify the molecular composition. Detailed concentration changes and oxygen isotropic mixtures identify the new molecular species O2KO2 and O2RbO2, the potassium and rubdium disuperoxide molecules which likely have the D2d structure. Force constants for the molecules synthesized here are compared with those reported earlier for LiO2 and NaO2.
TL;DR: Gradual changes were observed in the frequencies and intensities of characteristic amide bands over the relative humidity range of 0 to 75%, which lead to the conclusion that water molecules are gradually attached to peptide NH bonds within the triple helix over a wide range of relative humidity.
Abstract: The infrared spectra of undenatured bovine tendon collagen were investigated at 25°C and relative humidities from 0 to 95%. Suitable samples were prepared by forcing frozen suspensions of the material in distilled water through a stainless steel capillary. The samples were investigated by electron microscopy before and after the spectra were obtained to ascertain that no denaturation had taken place while the sample was exposed to infrared radiation. Temperature controlled absorption cells were constructed which permitted the passing of air with a known water content over the sample film. Gradual changes were observed in the frequencies and intensities of characteristic amide bands over the relative humidity range of 0 to 75%. These changes are particularly pronounced for the amide II band, associated with bending motions of peptide NH bonds. They lead to the conclusion that water molecules are gradually attached to peptide NH bonds within the triple helix over a wide range of relative humidity. Changes in CH deformation bands suggest that CH to O hydrogen bonding does occur and that it is more pronounced in collagen exposed to high relative humidity.
TL;DR: In this article, the infrared spectrum of the initial deposit shows an absorption between 1350 and 1375 cm−1 which can be assigned to the NO− stretching fundamental of Mx+NO− ion pairs, in good agreement with the vibrational spacing recently reported for groundstate NO− in the gas phase.
Abstract: The infrared spectra which result when samples of NO2 are codeposited with the various alkali metals in an argon matrix at 4 or at 14°K are consistent with the occurrence of strong charge‐transfer interaction. In addition to isolated NO2−, previously identified in this system, ion pairs of general formula Mx+NO2− are stabilized. When NO is substituted for NO2, the infrared spectrum of the initial deposit shows an absorption between 1350 and 1375 cm−1 which can be assigned to the NO− stretching fundamental of Mx+NO− ion pairs, in good agreement with the vibrational spacing recently reported for ground‐state NO− in the gas phase. Weak charge‐transfer interaction occurs between alkali‐metal atoms and N2O in an argon matrix environment. Results of the present experiments can be explained by postulating that the upper, predominantly ionic state of the charge‐transfer complex decomposes producing O−, which may diffuse through the matrix. A new absorption which appears at 1205 cm−1 has tentatively been assigned ...
TL;DR: In this paper, the absorption spectra of silica gel were measured in order to assign the bands senstive to adsorption at 870 and around 950 cm−1.
Abstract: Infrared absorption spectra of the systems of silica gel - H216O,D216O,H218O, and some organic vapors were measured in order to assign the bands senstive to adsorption at 870 and around 950 cm−1. Deuteration of silica gel caused the absorption decrease at 870 cm−1 and the appearance of a band at 620 cm−1. The band around 950 cm−1 appearing by adsorption not only of water but also of organic vapors showed no shift on deuteration, but shifted toward low frequency side by 25 cm−1 on the substitution of 16O of surface silanol groups with 18O. From these facts the bands at 870, 620 and 950 cm−1 were assgned to Si–OH bending, Si–OD bending and Si–O stretching vibrations of surface silanol groups, respectively. The oxygen atom of silanol groups of silca gel was found to exchange with that of adsorbed water molecules even at room temperature for a sample treated at temperature below 300°C. On the other hand, higher reaction temperature of ca. 200°C was necessary for a sample calcined at 800°C. mechanism of the ox...
TL;DR: In this article, a complete vibrational assignment is proposed on the basis of gas-phase band contours, depolarization ratios and dichroic ratios; it is found that although the molecule has C2 symmetry in all three states of aggregation, the liquid and vapour-phase spectra are explainable in terms of C2v pseudo-symmetry.
Abstract: Saturn satellites spectrophotometric observations at UV, visible and near IR, noting reflection spectra data
Journal Article•
Abstract: Frequencies of the normal modes of vibration for a long chain (Si:Oo)" molecule in both infrared and far infrared absorption spectra of diopside were calculated on the basis of the Urey-Bradley force field and compared withthose measured. The wave numbers calculated were found to be in good agreement with those measured. The force constants obtained for the Si:Oo moiecule were Ka 5.0, K" 4.5, I1o 0.4, .F-narsis;y 0.4, Fas166; 0.1, 4,0.1, Fn" 0.05, Faa -0.9 and Fa, -0.9 md /A.
TL;DR: In this paper, a normal coordinate analysis was performed on chloro complexes employing a Urey-Bradley force field with resonance parameter and suitable general valence force field terms about the metal site.
TL;DR: In this article, the bending force constants of the gas phase complexes HCN-HF, DCN-DF and four isotopic species of CH$3}$CN-HF have been measured over the range 200 to 4000 cm$-1}$.
Abstract: The infrared spectra of the gas phase complexes HCN-HF, DCN-DF and four isotopic species of CH$_{3}$CN-HF have been measured over the range 200 to 4000 cm$^{-1}$. Two bands have been observed, one associated with the stretching vibration of HF in the complex and the other with a bending vibration of the hydrogen bond itself. At higher resolution both bands show fine structure which has been interpreted as being a series of hot bands associated with transitions from excited levels of another low-frequency bending vibration of the hydrogen bond. In the first band the peaks are P branch bandheads in the individual hot bands and in the second band they are sharp Q branches. From temperature studies of these bands and from the effects of isotopic substitution on the spacing of the fine structure the frequency of the lower bending vibration has been determined. Further structure in the first band gives the frequency of the stretching vibration of the hydrogen bond itself. A complete assignment of all the vibrations associated with the hydrogen bond has therefore been made. From the frequencies of the two bending motions (555 and 70 cm$^{-1}$ for the HCN-HF complex) values of the bending force constants have been calculated. Several anharmonic constants have also been measured and the effect of anharmonicity on the breadth of bands associated with the hydrogen bond is discussed.
TL;DR: In this paper, the infrared spectra of 2,2'-bipyridine and its deutero analogue were obtained from 4000 to 40 cm−1 and the absorption bands of these compounds were assigned by a comparison of their spectra to each other as well as to the structurally similar molecules: pyridine, 2-substituted pyridines and biphenyl.
TL;DR: In this article, photolysis of samples of HCCl3 isolated in an argon matrix at 14°K using 1216-A radiation leads not only to the isolation of a high yield of CCl3, but also to the photoionization of CCL3, resulting in the stabilization of a sufficient concentration of cCl3+ for direct infrared spectroscopic identification.
Abstract: Photolysis of samples of HCCl3 isolated in an argon matrix at 14°K using 1216‐A radiation leads not only to the isolation of a high yield of CCl3, but also to the photoionization of CCl3, resulting in the stabilization of a sufficient concentration of CCl3+ for direct infrared spectroscopic identification. The assignment of still other infrared absorptions which appear in this system to negatively charged species has been confirmed by experiments in which a small concentration of an alkali metal atom is also present in the matrix, providing a photoelectron source. When matrix‐isolated HCCl3 is subjected to photolysis by 1067‐A argon resonance radiation, very little CCl3 is produced, but HCCl2, HCCl2+, and the same negatively charged species are stabilized in significant concentration. Studies of chloroform samples enriched in carbon‐13 and of DCCl3 samples have provided support for these identifications and have yielded data necessary for obtaining several of the force constants of these species. The infr...