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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.
51

Vibrational sum frequency spectroscopic investigations of the structure, hydrogen bonding, and orientation of water molecules at the liquid/liquid interface /

Scatena, Lawrence Francis. January 2001 (has links)
Thesis (Ph. D.)--University of Oregon, 2001. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 146-152). Also available for download via the World Wide Web; free to University of Oregon users.
52

Double point contact single molecule absorption spectroscopy

Howard, John Brooks. January 2009 (has links)
Thesis (Ph.D)--Physics, Georgia Institute of Technology, 2010. / Committee Chair: Marchenkov, Alexei; Committee Member: Davidovic, Dragomir; Committee Member: Gole, James; Committee Member: Hunt, William; Committee Member: Reido, Elisa. Part of the SMARTech Electronic Thesis and Dissertation Collection.
53

Rotation-vibration spectroscopy of certain symmetric top molecules

Paso, Risto. January 1985 (has links)
Thesis--University of Oulu, 1985. / Includes bibliographical references (p. [48]-49).
54

Ligand isotope vibrational spectroscopic and DFT studies of Pt(II) and Cu(I) complexes /

Medina, Gerardo Juan. January 2004 (has links)
Thesis (Ph. D. (Chemistry))--Rhodes University, 2005.
55

Vibrational spectroscopy in cryogenic solutions application of thermal lensing and Fourier transform techniques to the study of molecular C-H overtone transitions /

Lopez-Calvo, Alfredo. Manzanares, Carlos E. January 2006 (has links)
Thesis (Ph. D.)--Baylor University, 2006. / Includes bibliographical references (p. 230-241).
56

Eckart frame motions and molecular vibrations

Meyer, Frederick O. 12 1900 (has links)
This dissertation deals with motions of the Eckart frame in relation to molecular vibrations. The angular motion and the angular acceleration of the Eckart frame are treated. A technique for taking the first and second differentials of real symmetric eigenvalue problems is developed. This technique is applied to the first differential of the Eckart frame matrix.
57

The spectroscopy of polyatomic molecules : the vibration-rotation spectra of the methyl acetylenes

Thomas, R. K. January 1968 (has links)
No description available.
58

The spectroscopy of polyatomic molecules

Griffiths, Peter R. January 1967 (has links)
No description available.
59

Ligand isotope vibrational spectroscopic and DFT studies of Pt(II) and Cu(I) complexes

Medina, Gerardo Juan January 2005 (has links)
Ligand-isotope labelling studies were performed on Zeise’s salt derivatives with pyridine N-oxide and quinoline N-oxide, their perdeuterated and O-18 isotopomers, C₂D₄ and ¹³CO, and the results of the vibrational analyses are reported. The isotopomers are modelled utilizing DFT calculations at the B3LYP level with the 6-31 G** basis set, and a pseudopotential level for the Pt atom. The calculated and observed structure and vibrational spectra correlate well. The crystal structures of [Pt(C₂2H₄)(pyO)Cl₂] and [Pt(CO)(quinO)Br₂] are reported. The frequency for the νPt-O vibration, ambiguously assigned in the literature, is here assigned unequivocally at 400 cm⁻¹. Previously observed, but inadequately described phenomena are addressed: the νN-O vibration in substituted quinoline N-oxides has been assigned previously at significantly different frequencies, depending on the nature of the substituent. This suggests that there is no specific mid-ir band associated with a high N-O character. A suitable explanation is presented for this phenomenon, showing that in low symmetry systems (eg. quinO) the N-O stretch is dispersed among several modes, whereas in high symmetry systems (eg. pyO) only a few limited modes have a high N-O character. A theoretical study of Cu(I) carbonyl compounds with macrocyclic ligands is presented. Local and global HSAB parameters applied to the donor and Cu atoms are used to explain the observed reactivities and the available spectroscopic data. Extended to [Cu(CO){H₂N(CH₂)[subscript n]NH(CH₂)[subscript m] NH₂}] BPh₄ (where n = 2, m = 2, 3 and n =3, m = 3, 4) and their -d₅ and ¹³CO isotopomers, subtle differences obtained experimentally for the CO stretching frequency in this series have been reproduced in the DFT calculations at the B3LYP level, using the 6-31 G* and 6-31 G** basis sets. Several properties (ligand pK[subscript a] values, νCO frequencies, etc.) correlate with some HSAB descriptors. Vibrational analyses are presented of Cu(I) carbonyl Schiff-base derivatives of N-Benzylidene-N’-[2-(benzyilidene-amino)-ethyl]-ethane-1,2-diamine, {2,2N3(C₆H₄R)₂}, and their -d₅ and ¹³CO isotopomers. The crystal structure of [Cu(CO){2,2N3(C₆H₅)₂}]BPh₄ is reported. From geometry optimizations and the HSAB descriptors, spectroscopic trends ([n]Cu-N and [nu]CO) are related to calculated global hardness and the Hammett substituent parameters, and are discussed in terms of σ-donation and π-backbonding of Cu- CO.
60

Toward Understanding the Vibrational Spectra of BEDT-TTF, a Scaled Density Functional Force Field Approach

Liu, Ruifeng, Zhou, Xuefeng, Kasmai, H. 30 July 1997 (has links)
Density functional theory B3LYP and ab initio MP2 calculations were carried out to study the structures and vibrational spectra of bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and the related compounds, 1,3-dithiole-2-thione (DTT), tetrathiafulvalene (TTF), and 4,5-ethylenedithio-1,3-dithiole-2-thione (EDT-DTT). It is found that B3LYP functional overestimates C-S bond lengths significantly and underestimates frequencies of modes involving C-S stretching accordingly. The errors in B3LYP force fields are shown to be satisfactorily corrected by scaled quantum mechanical force field procedure. After applying the scale factors derived from DTT, the scaled B3LYP force fields reproduce the observed frequencies of TTF, EDT-DTT, and BEDT-TTF satisfactorily, with a mean deviation between the calculated and observed frequencies of less than 10 cm-1. On the basis of agreement between the calculated and observed frequencies, isotope shifts, as well as IR and Raman intensities, assignments of the fundamental vibrational modes of these molecules are given in terms of the true molecular symmetries of the equilibrium structures. This study shows that the scaled density functional force field procedure is a powerful approach for understanding the spectral features of large and low symmetry molecules.

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