Absorption spectra, polarized

The order parameter of SDl is equal to -0.4 at = 372 nm (absorption maximum), which is 80% of its maximum absolute value (S = -0.5 in our case). 

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Tabic 6-3. Vibrational assignment of the b- and c-polarized absorption spectra of T6 single crystal at 4.2 K. The proposed assignment is in agreement with the most intense vibrational modes found by Bimbaum et al. [64] in the excitation spectra of matrix isolated tetralhiophene (T4) at low temperature. 

We examined the magnetic orientation or organization of the SWNTs or the polymer-wrapped SWNTs using MEHPPV by measurements of AFM images and polarized absorption spectra [46-48]. 

Figure 15.2 Polarized absorption spectra of SWNT/MEHPPV composites on glass plates in (a) the absence (OT) and (b) the presence of magnetic processing (8T). In the absence of magnetic processing (OT), the polarization direction of the light against the longitudinal direction of the glass plates is horizontal...

The above results of polarized absorption spectra on glass plates support the magnetic orientation ofthe SWNT/MEHPPV composites and the shortened SWNTs in the absence and presence of NaHC03, where the composites or the SWNTs were oriented with the tube axis of the composites or the SWNTs parallel to the magnetic field (8T), suggested by the results ofthe AFM images (Figure 15.1). 

On the basis of the polarized absorption spectra (Figure 15.2), the magnetic orientation of SWNT/MEHPPV composites can also most likely be ascribed to the anisotropy in susceptibilities of SWNTs, similar to the comparison of the AFM images (Figure 15.1), as described above. 

Rosell FI, Boxer SG (2003) Polarized absorption spectra of green fluorescent protein single crystals Transition dipole moment directions. Biochemistry 42 177-183... 

The angular dependence of the polarized absorption spectra of LB films containing AMP deposited at lower (20 mN m1) and higher (43 or 50 mN m 1) surface pressures was studied to determine the molecular orientation of porphyrins as schematically shown in Figure 5. No polarization angle (a) dependence was observed at normal incidence. This indicates that the projections of the transition dipole moments of the porphyrins are statistically... 

Fig. 9 a Observation of intercalation of ethidium bromide into the DNA-lipid film in an aqueous solution, and polarized absorption spectra of the ethidium-intercalated stretched DNA-lipid film b in the wet state and c in the dry state. Ethidium bromide was intercalated one molecule per 10 base-pairs at 25 °C. Open, two-headed arrows show the stretching direction of the film... 

When a polarized spectrum of the film was taken in the dry state, a small dichroic ratio was observed (A L/A// = 1.3, see Fig. 9c). This is due to the slant structures of base pairs and intercalated dyes to the axis of the strands, since the DNA strands were confirmed to be aligned along the stretching direction even in the dry film (see Fig. 7c). These changes of polarized absorption spectra dependent on water moisture were reversible at least 10 times. 

The LB film of the DNA-/profiavine/2C18-glu-N complex was transferred with 44 layers (22 cycles) on one side of a glass plate (total 88 layers on both sides) and measured by polarized absorption spectra in aqueous solution (see Fig. 11a). The LB film did not swell and did not remove from the substrate... 

Fig. 11 Polarized absorption spectra of DNA /proflavine/2Ci8-glu-N LB films (88 layers) deposited by a vertical dipping method and b horizontal lifting method...

Figure 23-9 Polarized absorption spectra of orthorhombic crystals of cytosolic aspartate aminotransferase. The light beam passed through the crystals along the b axis with the plane of polarization parallel to the a axis (A) or the c axis (C). Left, native enzyme at pH 5.4 right, enzyme soaked with 300 mM 2-methylaspartate at pH 5.9. The band at 430 nm represents the low pH proto-nated Schiff base form of the enzyme. Upon soaking with 2-methylaspartate the coenzyme rotates 30° to form a Schiff base with this quasisubstrate. The result is a large change in the c/a polarization ratio. The 364 nm band in the complex represents the free enzyme active site in the second subunit of the dimeric enzyme.70,73 Courtesy of C. M. Metzler.

Polarized absorption spectra are often expressed in terms of the dichroic ratio,... 

Figure 3.3 Polarized absorption spectra of the tetragonal mineral gillespite, BaFe2+Si4OI0, measured with light polarized parallel and perpendicular to the c crystallographic axis (see 3.8.1).-E c spectrum ..E-Lc spectrum.

Figure 3.16 Energy level diagram for ferric iron matched to spin-forbidden crystal field transitions within Fe3+ ions, which are portrayed by the polarized absorption spectra of yellow sapphire (adapted from Ferguson Fielding, 1972 Sherman, 1985a). Note that the unassigned band at -17,600 cm-1 represents a paired transition within magnetically coupled Fe3+ ions located in adjacent face-shared octahedra in the corundum structure.

Figure 3.18 Three ways of measuring the polarized absorption spectra of a uniaxial crystal.

Figure 4.2 Polarized absorption spectra of the titanian subsilicic diopside (fassaite)...

Figure 4.3 Polarized absorption spectra of piemontite.a spectrum ----------P spectrum -----y spectrum. The epidote mineral, containing 0.625 Mn3+ ions per formula...

Figure 4.5 Energy level diagram for the Mn3+ ion in the M3 site of the epidote structure. Observed transitions refer to the polarized absorption spectra shown in fig. 4.3.

Figure 4.8 Polarized absorption spectra of manganiferous olivines of the fayalite-tephroite series, (a) Fayalite, Fa TejFop (b) knebellite, Fa69Te26Fo5 (c) tephroite, Fa31Te67Fo2 (d) tephroite, FajTe Foj. The reduced relative intensity of the absorption band at 1,078 to 1,120 nm is due to substitution of Fe2+ by Mn2+ in M2 positions of the olivine structure, [y spectra y=a.]...

Figure 4.10 Polarized absorption spectra of ruby (from Bums, 1984). The ruby formula is (AIq 99gCr0 002)203, and the spectra originate from crystal field transitions within Cr3+ replacing Al3+ ions in trigonally distorted octahedral sites in the trigonal corundum structure. Consequently, the spectra differ slightly for light polarized (a) parallel (Ellc) and (b) perpendicular (E c) to the c crystallographic axis. The group theoretical assignments of the absorption bands are also indicated. [Reproduced from Chemistry in Britain, 1984, p. 1004]...

Figure 4.11 Polarized absorption spectra of vanadium-bearing zoisite (modified from Faye and Nickel, 1969). The zoisite from Tanzania contains 0.012 V3+ ions per formula unit, (a) Spectrum (A) y-spectrum of unheated zoisite Spectrum (B) y-spectrum of zoisite (now tanzanite) after heating to 600 °C Spectrum (C) unpolarized spectrum of tanzanite. (b) Spectrum (A) (1-spectrum of unheated zoizite Spectrum (B) p-spectrum of tanzanite after heating to 600 °C. [Optic orientation 0C = b P = c y = a.]...

Figure 4.12 Polarized absorption spectra of a vivianite single crystal measured in three zones of increasing oxidation. (1) Nearly colourless (2) light blue and (3) dark blue. The spectra were measured with light polarized along the b axis corresponding to the Fe2+-Fe3+ vector of edge-shared [FeOg] octahedra. Note the intensification of the Fez+ crystal field bands at 1,200 nm and 800 nm by the Fe2+ — Fe3+ IVCT at 630 nm (from Amthauer and Rossman, 1984).

Figure 4.16 Polarized absorption spectra of natural and synthetic sapphires (from Bums and Bums, 1984a). (a) Natural yellow sapphire (b) natural dark blue sapphire (c) synthetic Ti-doped A1203 (d) synthetic Fe-Ti-doped A1203. —Ellc spectra -----EJx...

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