Molecule in Soft-Crystal at Ground and Excited States: Theoretical Approach

Abstract The CNDO/2 CI method was used for the examination of 1,4-dioxane and 1,4-dioxane-water complexes (2:1), taking into account various conformations of the dioxane molecule. The energies of the molecules in the ground and excited states, the energies of hydrogen bond formation, the dipole moments, the transition moments, and the oscillator strengths for both the complexed and isolated 1,4-dioxane molecules were evaluated. The results of these studies are used to reveal the influence of water on the features of energy transfer from excited, by y-radiation, 1,4-dioxane or dioxane-water complexes to the luminophor.

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Vuv Spectra Y to Mo

International Astronomical Union Colloquium ◽

10.1017/s0252921100107808 ◽

1988 ◽

Vol 102 ◽

pp. 239

Author(s):

M.S.Z. Chaghtai

Keyword(s):

Excited States ◽

Spectral Analyses ◽

Vuv Spectra

Using R.D. Cowan’s computations (1979) and parametric calculations of Meinders et al (1982), old analyses are thoroughly revised and extended at Aligarh, of Zr III by Khan et al (1981), of Nb IV by Shujauddin et Chaghtai (1985), of Mo V by Tauheed at al (1985). Cabeza et al (1986) confirmed the last one largely.Extensive studies have been reported of the 1–e spectra, Zr IV (Rahimullah et al 1980; Acquista and Reader 1980), Nb V (Shujauddin et al 1982; Kagan et al 1981) and Mo VI (Edlén et al 1985). Some interacting 4p54d2levels of these spectra have been reported from our laboratory, also.Detailed spectral analyses of transitions between excited states have furnished complete energy values for J ≠ 1 levels of these spectra during 1970s and 80s. Shujauddin et al (1982) have worked out Nb VI and Tauheed et al (1984) Mo VII from our lab, while Khan et al (1981) share the work on Zr V with Reader and Acquista (1979).

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Differential polarization imaging of sickled cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100102390 ◽

1988 ◽

Vol 46 ◽

pp. 62-63

Author(s):

Marcos F. Maestre

Keyword(s):

Optical Properties ◽

Theoretical Approach ◽

Polarized Light ◽

Polarization Microscopy ◽

Spectroscopic Techniques ◽

Polarization Imaging ◽

Circularly Polarized Light ◽

Circularly Polarized ◽

Microscopic Scale ◽

Chiral Structures

Recently we have developed a form of polarization microscopy that forms images using optical properties that have previously been limited to macroscopic samples. This has given us a new window into the distribution of structure on a microscopic scale. We have coined the name differential polarization microscopy to identify the images obtained that are due to certain polarization dependent effects. Differential polarization microscopy has its origins in various spectroscopic techniques that have been used to study longer range structures in solution as well as solids. The differential scattering of circularly polarized light has been shown to be dependent on the long range chiral order, both theoretically and experimentally. The same theoretical approach was used to show that images due to differential scattering of circularly polarized light will give images dependent on chiral structures. With large helices (greater than the wavelength of light) the pitch and radius of the helix could be measured directly from these images.

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