Infrared Intensity Measurements of Cryodeposited Thin Films of NH3, NH4HS, H2S, and Assignments of Absorption Bands

Interferometric infrared spectral transmission measurements from 60 to 10 000 cm−1 were made for thin films of NH3, NH4HS, and H2S cryodeposits, and recorded as a function of thickness and temperature from 88 K to evaporation points. Integrated band intensities were measured and are reported for all major absorptions. Assignments for lattice and internal fundamental modes are discussed. Particular attention is devoted to the various reported phases of solid NH3, and it is concluded that three phases are supported by experimental evidence: the stable cubic phase, a low temperature amorphous phase, and an intermediate temperature metastable phase. Results and changes of the spectra as a function of temperature will be summarized. Intercomparisons of the spectra obtained for the three cryodeposits are made.

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Simulations of the accuracy in retrieving stratospheric aerosol effective radius, composition, and loading from infrared spectral transmission measurements

Applied Optics ◽

10.1364/ao.45.002014 ◽

2006 ◽

Vol 45 (9) ◽

pp. 2014 ◽

Cited By ~ 9

Author(s):

Helen M. Steele ◽

Annmarie Eldering ◽

Jerry D. Lumpe

Keyword(s):

Stratospheric Aerosol ◽

Effective Radius ◽

Spectral Transmission ◽

Infrared Spectral ◽

Transmission Measurements

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Absolute Infrared Intensity Measurements in Thin Films

The Journal of Chemical Physics ◽

10.1063/1.1732118 ◽

1961 ◽

Vol 35 (5) ◽

pp. 1617-1620 ◽

Cited By ~ 39

Author(s):

Shiro Maeda ◽

P. N. Schatz

Keyword(s):

Thin Films ◽

Intensity Measurements ◽

Infrared Intensity

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A spectroscopic study of proton transfer and photochromism in N-(2-hydroxybenzylidene)aniline

Canadian Journal of Chemistry ◽

10.1139/v82-237 ◽

1982 ◽

Vol 60 (13) ◽

pp. 1738-1746 ◽

Cited By ~ 50

Author(s):

J. W. Lewis ◽

C. Sandorfy

Keyword(s):

Double Bond ◽

Low Temperature ◽

Infrared Spectrum ◽

Spectroscopic Study ◽

Title Compound ◽

Spectral Characteristics ◽

Absorption Bands ◽

Central Carbon ◽

Infrared Spectral ◽

Nitrogen Double Bond

The infrared spectral characteristics of N-(2-hydroxybenzylidene)aniline, its deuterium substituted analogue, N-(2-hydroxybenzylidene)-m-toluidine, and their photoproducts have been investigated. The infrared spectrum of a low temperature polycrystalline film of N-(2-hydroxybenzylidene)aniline exhibits new absorption bands at 3380, 1646, 1537, 1502, 1319, and 1310 cm−1 upon irradiation at 365 nm. Likewise, the spectrum of the m-toluidine derivative exhibits new absorption bands at 3320, 1650, 1535, 1503, 1321, 1310, and 995 cm−1 upon irradiation at 365 nm. These new data, in conjunction with the newly acquired data on the hydrochloride and deuterochloride of the title compound, indicate that the photoproduct is a zwitterion, not an ortho-quinone. It is also inferrred that the photoproduct exists in a conformation which is cis about the central carbon–nitrogen double bond.

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Absolute Infrared Intensity Measurements in Thin Films. II. Solids Deposited on Halide Plates

The Journal of Chemical Physics ◽

10.1063/1.1734216 ◽

1963 ◽

Vol 39 (12) ◽

pp. 3474-3481 ◽

Cited By ~ 29

Author(s):

S. Maeda ◽

G. Thyagarajan ◽

P. N. Schatz

Keyword(s):

Thin Films ◽

Intensity Measurements ◽

Infrared Intensity

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Infrared Intensities of Liquids XIX: A Simple and Effective Approximate Method for the Calculation of Infrared Optical Constant Spectra of Liquids from Transmission Measurements

Applied Spectroscopy ◽

10.1366/0003702963905367 ◽

1996 ◽

Vol 50 (8) ◽

pp. 1039-1046 ◽

Cited By ~ 8

Author(s):

John E. Bertie ◽

Yoram Apelblat

Keyword(s):

Approximate Method ◽

Alkali Halide ◽

Optical Constants ◽

Refractive Indices ◽

Absorption Bands ◽

Infrared Intensity ◽

Liquid Cell ◽

Infrared Intensities ◽

Transmission Measurements ◽

Window Material

A simple and effective approximate method is presented for the calculation of the optical constants of neat liquids from transmission measurements. The method calculates the apparent absorbance due to reflection losses by treating the liquid cell as a single slab of the window material. This approach makes the method far simpler than the exact iterative method that has been used to develop secondary infrared intensity standards and that applies Fresnel's equations to each interface in the cell. However, for all but the strongest absorption bands, the approximate method gives imaginary refractive indices that are within ∼1% of those from the exact method. The method is, thus, useful for nearly all common liquids in cells with alkali halide windows for all but the strongest bands. The effect of the size of the mismatch between the real refractive indices of sample and windows has been explored to some extent. It is recommended that results from the approximate method be regarded with caution if the refractive indices of the sample and windows differ by more than 0.15.

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Influence of L-Tryptophan on Growth and Optical Properties of PbS Nanocrystalline Thin Films

Journal of Nanomaterials ◽

10.1155/2018/3431942 ◽

2018 ◽

Vol 2018 ◽

pp. 1-15 ◽

Cited By ~ 3

Author(s):

R. Palomino Merino ◽

R. Gutiérrez Pérez ◽

P. Trejo García ◽

L. Chaltel Lima ◽

O. Portillo Moreno ◽

...

Keyword(s):

Thin Films ◽

Morphological Changes ◽

Band Gap Energy ◽

Undoped Sample ◽

Cubic Phase ◽

Electronic Charge ◽

Absorption Bands ◽

Scherrer Formula ◽

Xrd Patterns ◽

Nanocrystalline Thin Films

The growth through the green chemical bath of PbS doped systematically with the biomolecule L-tryptophan led to growth of hybrid, inorganic-organic, nanocrystalline thin films onto glass slides at T~80°C. The thickness was found in the range of 230–140 nm. Morphological changes were analyzed using atomic force microscopy (AFM). FTIR (Fourier-transform infrared spectroscopy) spectra showed broad absorption bands located at ~3450 cm−1 attributed to stretching of the H2O molecules and two small absorption bands located at ~2285 cm−1 and ~2918 cm−1 along with a strong band at ~1385 cm−1 assigned to vibration modes corresponding to CO32− ions. In the patterns of X-ray diffraction (XRD), the cubic phase was identified in all the samples according to the angular positions 2θ~26.08°, 30.13°, 43.08°, 51.91°, 53.60°, 6251°, 68.98°, and 71.15°. Using the Scherrer formula on the XRD patterns, the grain size (GS) was determined; for the undoped sample, ~42 nm was found, whereas for the doped samples, ~42–22 nm was found. The electronic charge distribution of L-tryptophan was determined using the molecular electrostatic potential (MEP) to understand the decrease on the GS associated with the interaction of π electrons from conjugated rings and amino-acid functional groups. The absorbance spectra in doped films showed excitonic peaks at ~1.8–2.1 eV associated to a higher energy of the 1Sh → 1Sh and 1Ph → 1Pe electronic transitions. Through optical absorption, a shift for the band gap energy was observed from ~1.4 eV for the undoped sample and ~2.1–2.3 eV for the doped films, respectively. Such behaviour is generally associated with the GS decrease and the effect of quantum confinement; a simple model by calculating changes in Gibbs free energy (ΔG°) for growth of nanocrystals is presented.

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Observation by HVEM of the martensite transformation and the superconducting transition in Nb3Sn

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106004 ◽

1988 ◽

Vol 46 ◽

pp. 788-789

Author(s):

M. A. Kirk ◽

M. C. Baker ◽

B. J. Kestel ◽

H. W. Weber

Keyword(s):

Thin Films ◽

Low Temperature ◽

Superconducting State ◽

Martensite Transformation ◽

Sputter Deposition ◽

Diffusion Reaction ◽

Solute Diffusion ◽

Superconducting Transition ◽

Twin Boundaries ◽

Martensite Structure

It is well known that a number of compound superconductors with the A15 structure undergo a martensite transformation when cooled to the superconducting state. Nb3Sn is one of those compounds that transforms, at least partially, from a cubic to tetragonal structure near 43 K. To our knowledge this transformation in Nb3Sn has not been studied by TEM. In fact, the only low temperature TEM study of an A15 material, V3Si, was performed by Goringe and Valdre over 20 years ago. They found the martensite structure in some foil areas at temperatures between 11 and 29 K, accompanied by faults that consisted of coherent twin boundaries on {110} planes. In pursuing our studies of irradiation defects in superconductors, we are the first to observe by TEM a similar martensite structure in Nb3Sn.Samples of Nb3Sn suitable for TEM studies have been produced by both a liquid solute diffusion reaction and by sputter deposition of thin films.

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