An Infrared Spectroscopic Study of Quantum Diffusion in Solid Hydrogen

1973 ◽  
Vol 51 (18) ◽  
pp. 1910-1914 ◽  
Author(s):  
S. A. Boggs ◽  
H. L. Welsh
Keyword(s):  
Absorption Band ◽  
Spectroscopic Study ◽  
Concentration Dependence ◽  
Rate Constant ◽  
Infrared Absorption ◽  
Experimental Error ◽  
Infrared Spectroscopic Study ◽  
Quantum Diffusion ◽  
Good Agreement ◽  
Infrared Data

The fundamental infrared absorption band of almost pure solid parahydrogen was investigated for evidence of quantum diffusion of orthohydrogen molecules. A feature of the band, involving a reorientation of neighboring o-H2 pairs, was observed to increase as a function of the time after solidification. The rate constant characterizing the diffusional formation of o-H2 pairs was found to lie in the range 0.3–0.7 h−1 for o-H2 concentrations of 0.7–1.6% and temperatures 1.14–2.10 K. The values and concentration dependence of the rate constant are in good agreement with the theory of Oyarzun and Van Kranendonk. The infrared data also agree within the experimental error with NMR observations of Amstutz, Thompson, and Meyer.

Fundamental infrared absorption features of α-quartz: An unpolarized single-crystal absorption infrared spectroscopic study

2019 ◽  
Vol 101 ◽  
pp. 52-63 ◽  
Author(s):  
Mingyue He ◽  
Wei Yan ◽  
Yedi Chang ◽  
Kexin Liu ◽  
Xi Liu
Keyword(s):  
Single Crystal ◽  
Spectroscopic Study ◽  
Infrared Absorption ◽  
Infrared Spectroscopic Study ◽  
Infrared Spectroscopic ◽  
Absorption Features

AN INFRARED-SPECTROSCOPIC STUDY OF METHYL IODIDE AND METHYLENE IODIDE ON Ag(111)

2001 ◽  
Vol 08 (03n04) ◽  
pp. 303-312 ◽  
Author(s):  
G. WU ◽  
D. STACCHIOLA ◽  
M. COLLINS ◽  
W. T. TYSOE
Keyword(s):  
Infrared Spectroscopy ◽  
Spectroscopic Study ◽  
Methyl Iodide ◽  
Metastable State ◽  
Infrared Spectroscopic Study ◽  
Random Orientation ◽  
Methylene Iodide ◽  
Bending Mode ◽  
Reflection Absorption Infrared Spectroscopy ◽  
Infrared Data

The adsorption of methylene iodide and methyl iodide is studied on Ag(111) using reflection-absorption infrared spectroscopy. Molecular methylene iodide adsorbs in a random orientation at 80 K and converts into a species with the H–C–H plane adsorbed perpendicular to the surface on heating to 155 K, and also dissociates into iodomethyl species. These undergo further decomposition eventually to form ethylene, although no methylene species are detected on the surface. Methyl iodide forms both multilayers and a metastable state on Ag(111) at 180 K, where the C–I axis of the metastable state is oriented nearly parallel to the surface. Infrared data suggest that the metastable state both desorbs almost simultaneously with the multilayer and converts to adsorbed methyl iodide with the C–I axis oriented nearly perpendicular to the surface. The latter species decomposes into adsorbed methyl fragments and adsorbed iodine where the frequency of the methyl bending mode for CH3(ads) and for CH3I(ads) are identical at 1230 cm -1.

H8Si8O12 Clusters on Si(100)-2×l and Gold: A Comparative Infrared Spectroscopic Study

1999 ◽  
Vol 567 ◽  
Author(s):  
Kenneth T. Nicholson ◽  
Mark A. Biscotto ◽  
Mark M. Banaszak Holl
Keyword(s):  
Spectroscopic Study ◽  
Local Symmetry ◽  
Infrared Spectroscopic Study ◽  
Gold Surfaces ◽  
Infrared Spectroscopic ◽  
Infrared Data

ABSTRACTReflection-absorption infrared data are presented for H8Si8O12 clusters chemisorbed to Si(100)-2×1 and evaporated gold surfaces. Peak assignments and the implications of the local symmetry imposed upon the cluster by the surface are discussed.

Infrared Studies of Quantum Diffusion in Solid Hydrogen

1974 ◽  
Vol 52 (24) ◽  
pp. 2451-2453 ◽  
Author(s):  
B. J. Roffey ◽  
S. A. Boggs ◽  
H. L. Welsh
Keyword(s):  
Rate Constant ◽  
Infrared Absorption ◽  
Reasonable Agreement ◽  
Solid Hydrogen ◽  
Quantum Diffusion ◽  
Infrared Studies ◽  
Absorption Measurements

The present work is an extension of the infrared absorption measurements by Boggs and Welsh on the quantum diffusion of o-H2 molecules in almost pure p-H2 solid. The new data, combined with the earlier data, were analyzed statistically. The rate constant which characterizes the formation of o-H2 molecular pairs was found to be in the range 0.3–0.7 h−1 for ortho concentrations of 0.7–1.8% and temperatures from 1.14 to 2.10 K. The results show reasonable agreement with the theory of Oyarzún and Van Kranendonk.

THE H2O-CH3F COMPLEX: A COMBINED MICROWAVE AND INFRARED SPECTROSCOPIC STUDY SUPPORTED BY STRUCTURE CALCULATIONS

2015 ◽  
Author(s):  
Elangannan Arunan ◽  
Olivier Pirali ◽  
T. Huet ◽  
Pierre Asselin ◽  
Pascale Soulard ◽  
...  
Keyword(s):  
Spectroscopic Study ◽  
Infrared Spectroscopic Study ◽  
Infrared Spectroscopic ◽  
Structure Calculations

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.

Infrared spectroscopic study of site symmetry effects for sulphite and sulphate anions in solid sodium sulphite oxidized by air oxygen

1985 ◽  
Vol 50 (12) ◽  
pp. 2715-2721
Author(s):  
Bohumil Hájek ◽  
Alexander Muck ◽  
Eva Šantavá
Keyword(s):  
Aqueous Solution ◽  
Spectroscopic Study ◽  
Sodium Sulphite ◽  
Site Symmetry ◽  
Infrared Spectroscopic Study ◽  
Infrared Spectroscopic

The mutual replacement of SO32- and SO42- anions was studied in Na2SO3.7 H2O crystals where sulphite is slowly oxidized to sulphate by air oxygen. In a series of Na2(SO3, SO4).7 H2O samples, the C1 or Cs site symmetry appears for the SO32- anion and the site symmetry of the SO42- anion is lowered gradually from Td through D2d or C3v to C1. The replacement was also studied for anhydrous sodium sulphite obtained by dehydration or by evaporation from aqueous solution. Despite the different structures of Na2SO3 and Na2SO4 crystals (C3i1 and D2h24, respectively), the favourable dimensions of the sterically different anions allow the SO42- ions, with their own symmetry Td, to be located in the C3 sites of the SO32- ions in Na2SO3.

A Near-Infrared Spectroscopic Study of 60 Micron Peakers

1999 ◽  
Vol 118 (5) ◽  
pp. 2038-2054 ◽  
Author(s):  
Charlene A. Heisler ◽  
Michael M. De Robertis
Keyword(s):  
Spectroscopic Study ◽  
Near Infrared ◽  
Infrared Spectroscopic Study ◽  
Infrared Spectroscopic

Infrared spectroscopic study of articular cartilage and synovial membrane

1987 ◽  
Vol 104 (5) ◽  
pp. 1535-1538
Author(s):  
S. M. Bychkov ◽  
M. M. Zakharova ◽  
S. A. Kuz'mina ◽  
V. P. Pavlov
Keyword(s):  
Articular Cartilage ◽  
Spectroscopic Study ◽  
Synovial Membrane ◽  
Infrared Spectroscopic Study ◽  
Infrared Spectroscopic
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