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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.
21

Vibration-internal rotation interactions in molecules containing a symmetric top group

January 1957 (has links)
P.R. Swan, Jr., M.W.P. Strandberg. / "March 22, 1956"--Cover. "Reprinted from Journal of molecular spectroscopy, volume 1, no. 4, December, 1957." / Bibliography: p. 378. / Army Signal Corps Contract DA36-039-sc-64637 Dept. of the Army Task 3-99-06-108 Project 3-99-00-100
22

Rotational magnetic moments of 1[Sigma] molecules

January 1951 (has links)
J.R. Eshbach [and] M.W.P. Strandberg. / "January 9, 1951." / Bibliography: p. 21. / Army Signal Corps Contract No. W36-039 sc-32037 Project No. 102B. Dept. of the Army Project No. 3-99-10-022.
23

Progress toward synthetic molecular motors : directed single bond rotation in a prototypical biaryl lactone system /

Lin, Ying. January 2007 (has links)
Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 109-124). Also available for download via the World Wide Web; free to University of Oregon users.
24

The design and synthesis of prototypical artificial molecular motors : studies of directed bond rotation in chiral biaryls /

Dahl, Bartholomew James, January 2007 (has links)
Thesis (Ph. D.)--University of Oregon, 2007. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 151-165). Also available for download via the World Wide Web; free to University of Oregon users.
25

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).
26

The search for correlated rotation in sterically hindered, multi-n-bladed carbon(n)argon(n)(x+/-) (n = 5, 6 and 7) propellers: from models to molecules /

Brydges, Stacey. McGlinchey, Michael J. January 2003 (has links)
Thesis (Ph.D.)--McMaster University, 2003. / Advisor: Michael J. McGlinchey. Includes bibliographical references (leaves 172-192). Also available via World Wide Web.
27

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

Thomas, R. K. January 1968 (has links)
No description available.
28

An Experimental Study of Collision Broadening of some Excited Rotational States of the Bending Vibration of Methyl Cyanide

Hajsaleh, Jamal Y. (Jamal Yousef) 05 1900 (has links)
A double modulation microwave spectrometer is used to evaluate the linewidth parameters for some excited rotational components in the bending vibration v_8 of 13CH3 13C 15N and 13CH3C15N isotopomers of methyl cyanide. The linewidth parameters for self-broadening of the ΔJ=2←1 rotational components for the ground v_8 , 1v_8, and the 2v_8 vibrations were determined over a pressure range of 1 to 13 mtorr and at a temperature of 300 K. The double modulation technique is used to explore the high eighth derivative of the line shape profile of the spectral line. This technique proved to give good signal-to-noise ratios and enabled the recovery of weak signals. An experimental method is developed to correct for source modulation broadening. The tests of the ratios of the two inner peak's separation of the eighth derivative of the line showed that they were up to 95% similar to those for a Lorentzian line shape function. The line shapes were assumed to be Lorentzian for the theoretical analysis of the derivative profiles and comparisons were made between experiment and theory on this basis. Dipole moments for vibrationally excited states were calculated from linewidth parameters and show systematic decrease with the increase of excitation. Impact parameters were calculated using the "hard sphere" model of the kinetic theory of gases. The results were many times larger than the size of the molecule itself. This suggests that the dominant interaction is a long range dipole-dipole force interaction.
29

A Comprehensive Model for the Rotational Spectra of Propyne CH₃CCH in the Ground and V₁₀=1,2,3,4,5 Vibrational States

Rhee, Won Myung 12 1900 (has links)
The energy states of C₃ᵥ symmetric top polyatomic molecules were studied. Both classical and quantum mechanical methods have been used to introduce the energy states of polyatomic molecules. Also, it is shown that the vibration-rotation spectra of polyatomic molecules in the ground and excited vibrational states can be predicted by group theory. A comprehensive model for predicting rotational frequency components in various v₁₀ vibrational levels of propyne was developed by using perturbation theory and those results were compared with other formulas for C₃ᵥ symmetric top molecules. The v₁₀=1,2,3 and ground rotational spectra of propyne in the frequency range 17-70 GHz have been reassigned by using the derived comprehensive model. The v₁₀=3 and v₁₀=4 rotational spectra of propyne have been investigated in the 70 GHz, and 17 to 52 GHz regions, respectively, and these spectral components assigned using the comprehensive model. Molecular constants for these vibrationally excited states have been determined from more than 100 observed rotational transitions. From these experimentally observed components and a model based upon first principles for C₃ᵥ symmetry molecules, rotational constants have been expressed in a form which enables one to predict rotational components for vibrational levels for propyne up to v₁₀=5. This comprehensive model also appears to be useful in predicting rotational components in more highly excited vibrational levels but data were not available for comparison with the theory. Several techniques of assignment of rotational spectra for each excited vibrational state are discussed. To get good agreement between theory and experiment, an additional term 0.762(J+1) needed to be added to Kℓ=1 states in v₁₀=3. No satisfactory theoretical explanation of this term has been found. Experimentally measured frequencies for rotational components for J→(J+1)=+1 (0≤J≤3) in each vibration v₁₀=n (0≤n≤4) are presented and compared with those calculated using the results of basic perturbation theory. The v₉=2 rotational spectrum of the propyne molecule was introduced in Appendix A to compare the rotational spectra of the same molecule in different vibrational levels v₉ and v₁₀.
30

HIGH RESOLUTION MICROWAVE STUDIES OF SMALL INORGANIC MOLECULES.

MURRAY, ALICE MARIE. January 1982 (has links)
High resolution rotational spectra of ¹⁰BH₃CO, ¹¹BH₃CO, ¹¹BD₃CO, PH₂D and CD₃CN were studied to obtain information concerning the electronic and magnetic properties of these molecules. From the analysis of the hyperfine structure of the rotational spectra of the molecules the following constants were determined: rotational constants (B₀), nuclear quadrupole coupling constants (eOq [x], spin-spin constants D (X-Y) and spin rotation constants (C[x]). The two instruments used in these experiments were a Stark modulated microwave spectrometer and a molecular beam maser spectrometer. The J = 0 to 1, F₁ = 3 to 3 and F₁ = 3 to 4 transitions of ¹⁰BH₃CO were studied. The molecular constants in KHz which were derived from the spectral analysis were: B(,0) = 8980060.3 (+/-) 1.0, eQqₐₐ (¹⁰B) = 3463.- (+/-) 8.0, C(¹⁰B) = .2 (+/-) .2, D(¹⁰B-H) = -2.8 (+/-) .2, D(H-H) = -7.2 (+/-) .5 and C(H) = 0.0 (+/-) .7. All three of the F₁ components of the J = 0 to 1 rotational transition of ¹¹BH₃CO were observed. The molecular constants in KHz which were obtained from the data analysis were: B₀ = 8657333.8 (+/-) .6, eQqₐₐ (¹¹B) = 1661.9 (+/-) 2.3, C(¹¹B) = .7 (+/-) .3, D(¹¹B-H) = 8.3 (+/-) .4, D(H-H) = -6.8 (+/-) .2 and C(H) = .4 (+/-) .4. Only spectra of the J = 0 to 1, F₁ = 3/2 to 3/2 transition of ¹¹BD₃CO were obtained. From the analysis of the spectra the following molecular constants were derived: eQqₐₐ (D) = -48.5 (+/-) 2.3, eQq(,zz)(D) = 116.9 (+/-) 5.4, C(D) = 0.0 (+/-) .8 and D(¹¹B-H) = -1.2 (+OR-) .3. The investigation of the 4₀₄ to 4₁₄ and 1₁₁ to 1₀₁ rotational transitions of PH₂D was unsuccessful in determining any molecular parameters. The spectra of the 4₀₄ to 4₁₄ rotational transition were not amenable to analysis and no spectra were obtained for the 1₁₁ to 1₀₁ rotational transitions. The three components of the J = 0 to 1 rotational transitions of CD₃CN were studied with the maser in the two cavity configuration. The constants in KHz which were determined were: B₀ = 7857978.7 (+/-) .1, eQqₐₐ(N) = -4229.2 (+/-) .6, eQqₐₐ(D) = -55.1 (+/-) .4, eQq(,zz)(D) = 165.5 (+/-) 5.0, C(,N) = 1.7 (+/-) .1 and C(,D) = 0.0 (+/-) .03.

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