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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Reactions of hydroxyl radicals in low-temperature matrices

Wiltshire, Karen Susan January 2003 (has links)
No description available.
2

Aluminium alkyls in low-temperature matrices

Kvisle, Steinar. January 1900 (has links)
Thesis (doctoral)--Universitetet i Oslo, 1983. / "Mars 1983." Includes bibliographical references.
3

Infrared Matrix Isolation Studies of The Reaction of Trimethylaluminum with Ozone

Phan, Huongtrandiep 13 April 2010 (has links)
No description available.
4

Generation and characterisation of some molecular compounds of the group 13 metals

Himmel, Hans-Jörg January 2000 (has links)
No description available.
5

Reactions and Photochemistry of Transition Metals with Methanol, Water, Hydrogen, and Carbon Monoxide via FTIR Matrix Isolation Spectroscopy

January 1988 (has links)
The reactions and photochemistry of atomic and diatomic transition metals with methanol, water, hydrogen, and carbon monoxide in noble gas matrices at cryogenic temperatures have been studied with the use of Fourier Transform infrared inert matrix spectroscopy. Atoms and dimers of iron and cobalt reacted with methanol to form the adducts, M(CH30H) and M2(CH30H), respectively. M(CH30H) underwent metal insertion into the 0-H bond of methanol to yield methoxymetal hydride, CH3OMH, with irradiation of the matrix in the violet (400 nm < λ < 500 nm) region. Ultraviolet (280 nm < λ < 360 nm) photolysis of the matrix rearranged CH30MH to yield the methylmetal hydroxide species, CH3MOH. CH30MH dissociated into carbon monoxide and hydrogen after prolonged irradiation in the ultraviolet region. Surprisingly, nickel atoms reacted spontaneously to insert into the 0-H bonds of methanol and water to form CH30NiH and HONiH, respectively. Violet photolysis caused CH30NiH to rearrange to form methylnickel hydroxide, CH3NiOH. This is effectively a two step process of the C-0 activation of methanol by a nickel atom. In addition to rearrangement, CH30NiH dissociates into carbon monoxide and hydrogen with violet photolysis. Nickel dimers also reacted spontaneously with water to form both an adduct and insertion products. Atomic nickel spontaneously inserts into the H-H bond of molecular hydrogen to yield a bent nickel dihydride, NiH2, in krypton and xenon matrices. Nickel dimers and trimers insert into the H-H bond of hydrogen to form Nix(H)2. In addition to the insertion products, nickel atoms, dimers, and trimers form adducts molecularly with hydrogen to yield complexes of the form Nix(H2)y, where x or y = 1-3. Reactions of iron with carbon monoxide in an argon matrix yielded the iron-carbonyl complexes, Fex(CO)y, where x = 1-3 and y = 1-2.
6

Vibrational spectroscopic studies of matrix isolated molecules

Evans, Richard January 1980 (has links)
The Raman spectrum of polycrystalline or matrix-isolated S<sub>2</sub>N<sub>2</sub> shows three bands attributable to its Raman active fundamentals, including two in close proximity; the possibility of Fermi resonance is discounted. The infrared spectrum.of polycrystalline S<sub>2</sub>N<sub>2</sub> shows five bands, including three attributable to the infrared active fundamentals, while the others are associated with some intermediate species in the polymerisation of S<sub>2</sub>N<sub>2</sub>. The vibrational spectra of matrix-isolated S<sub>4</sub>N<sub>4</sub> are consistent with previous observations in the solid state and in solution, also with the established cage structure of the molecule. The stretching force constants of S<sub>2</sub>N<sub>2</sub> and S<sub>4</sub>N<sub>4</sub>, lower than those predicted on the basis of observations on acyclic S-N molecules, are correlated with the strain in the molecules and their associated thermodynamic instability. The interaction force constants indicate delocalised π-bonding, apparently more extensive in S<sub>2</sub>N<sub>2</sub>. Substantial cross-ring S-S bonding is evident in S<sub>4</sub>N<sub>4</sub>; S-S interactions in S<sub>2</sub>N<sub>2</sub> are apparently non-bonded and repulsive in nature. The infrared spectrum of matrix-isolated Cr0C1<sub>3</sub> contains bands attributable to the fundamentals of this molecule, along with several indicating the presence of Cr0<sub>2</sub>C1<sub>2</sub> and possibly other related molecules. The Raman spectrum shows just three strong bands, all below 250 cm<sup>-1</sup>, assumed to arise from the deformation fundamentals of Cr0C1<sub>3</sub>; the form of the spectrum is attributed to absorption or fluorescence. The force constants derived for Cr0C1<sub>3</sub> correspond closely to their counterparts in V0C1<sub>3</sub> and Cr0<sub>2</sub>C1<sub>2</sub>, suggesting similar force fields in the three molecules. The infrared spectrum of the volatile products of the reaction between PC1<sub>3</sub> and NaN<sub>3</sub> indicates the presence of several molecules, possibly including C1<sub>2</sub>PN<sub>3</sub> and oligomers of C1<sub>2</sub> P = N, although no definite conclusions are drawn. Spectroscopic evidence also suggests that the reaction between (CH<sub>3</sub>)<sub>2</sub>PC1 and NaN<sub>3</sub> yields (CH<sub>3</sub>)<sub>2</sub>PN<sub>3</sub> as a major product, although observations such as the effect of ultraviolet photolysis remain unexplained.
7

Laboratory studies of astrophysical molecules

Wang, Haiyan. January 2005 (has links)
Thesis (Ph. D.)--University of Florida, 2005. / Title from title page of source document. Document formatted into pages; contains 189 pages. Includes vita. Includes bibliographical references.
8

A STUDY OF THE HYDROGEN BONDING CHARACTERISTICS OF HYDROGEN PEROXIDE BY MATRIX ISOLATION VIBRATIONAL SPECTROSCOPY

Goebel, James Robert January 2000 (has links)
No description available.
9

Atom versus cluster reactivities for calcium and magnesium

Whetten, Alan Ray. January 1984 (has links)
Call number: LD2668 .T4 1984 W53 / Master of Science
10

An Electron Bombardment-Matrix Isolation Study of the Tropospheric Reactions of Toluene

Campbell, Sasha Erin 26 November 2013 (has links)
The tropospheric reactions of toluene, acting as a model VOC, are investigated using an electron bombardment-matrix isolation system coupled with Fourier transform infrared spectroscopy. Initial experiments to produce the hydroxyl radicals used to initiate the toluene reactions via electron bombardment of water-argon mixtures are performed. The effects of electron current, water concentration, and gas flow rate are investigated. A more efficient method of initiating the toluene reactions, by directly creating benzyl radicals through electron bombardment of toluene is then investigated, and the effects of toluene concentration and electron current on the production of the benzyl radicals is quantified. Benzyl radicals are successfully produced, and identified via FT-IR. The next step is the formation of benzylperoxy radicals, via electron bombardment of toluene-oxygen-argon gas mixtures. Experiments are performed using increasing concentrations of toluene and oxygen, in an attempt to observe the benzylperoxy radical. Two new absorptions are observed in the infrared spectra and are tentatively identified as due to the peroxy group on the benzylperoxy radical. Computational work is also performed to confirm that benzylperoxy radicals can in fact be produced from benzyl radicals and oxygen. The vibrational frequencies of the benzylperoxy radical are also calculated, and used to confirm the possibility that the new absorptions seen in the infrared spectra could in fact be due to benzylperoxy radicals. The overall results from this work demonstrate that it is likely to be possible to use electron bombardment-matrix isolation systems to investigate tropospheric reactions of volatile organics, and that further experiments could be enhanced by structural modifications to the system. / Thesis (Master, Chemistry) -- Queen's University, 2013-11-26 15:57:59.4

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