Poly calculated spectra

Fig. 24. Experimental and simulated ( H)- C cross-polarization spectra of poly-5-caprolactone nanospheres in aqueous suspension after 12 h freezing. The calculated spectrum reproduces the carbon spectmm of four different methylene groups based on the chemical shift anisotropy listed in Table 1. It represents a superposition of two fractions of different isotropic mobility (80% T=0.1 ms 20% r=0.007 ms).

Figure 21. Schematic drawing of the combination of two els poly-butadiene chains. The lower stick drawing is of the calculated spectrum, using the additivity relationships.

Figure 1.23 (a) Comparison of (upper) the experimental and (lower) the calculated 220 MHz spectra of the CH2 protons in free-radical poly(vinyl chloride) in chlorobenzene at 150°C. (b) Decomposition of the calculated spectrum into tetrad components. (Reprinted with permission from [59], as discussed in the text). 

Fig. 9.10 (A) Calculated contributions to the CD spectrum of a-helical poly-L-alanine from the lowest-energy n-x transition (a), the x-x transitirm polarized parallel to the helix axis (b), and the x-x transitions with perpendicular polarization (c and d). (B) The total calculated spectrum dashed curve) and the measured CD spectrum solid curve). The widths of the calculated bands were adjusted to optimize the agreement of the calculated and measured spectra. Adapted from [49]...

A study of the valence band photoelectron spectrum and the X-ray emission spectrum of poly(ethylene oxide) was carried out by Brena and co-workers [102] in order to understand the effect of conformation on the observed spectra. Up to 12 monomers were used in the calculations for the valence band photoelectron... 

Poly(2,5-pyridyl) commonly know as poly(pyridine) has been the subject of considerable research effort as it luminesces in the blue region of the spectrum and may have uses in light emitting diodes (LEDs). Vaschetto and co-workers [103] reported a series of calculations on the molecule and its oligomers. The calculations included both the B3LYP and B3P88 density functions, Hartree-Fock calculations and a periodic solid-state DFT calculation using linear muffin tintype orbitals (LMTO). 

Figure 14 The left hand side shows the band structures of poly(pyridine) calculated using a DFT-LMTO method for helical polymers. The right hand side shows its calculated density of states spectrum (solid line) and the experimental UPS spectrum (dashed line). The UPS spectrum was taken from Miyamae et al. [104]. Reproduced with permission from Vaschetto et al. [103], Figure 6. Copyright 1997 the American Chemical Society.

Figure 7 shows the quadratic Stark spectrum of a poly(methyl metacrylate) film doped with a azobenzene-linked amphiphile, 4-octadecyloxy-4 -nitroazobenzene. Using eq. (5) and the most characteristic spectral point on the AT/T curves, where dD/dX = 0 and d2D/dXa = 0, the value of Ap was evaluated to be 5.4 debye. Further, the p value of the azobenzene-linked amphiphile was calculated to be 24 x 10 30 esu at a fundamental wavelength of 1064 nm. The p values of azobenzene-linked amphiphiles employed in this study were evaluated by the procedure mentioned here. The values are listed in Table 2 in the section 1.1.1. 

Fig. 9.30 a) Normalized MALDI TOF mass spectrum of all fractions (taken after 2 h to 72 h of polymerization time) of poly(2-phenyl-2-oxazoline) freed by dissolving the gold core with NaCN solution and collection of the polymer. The calculated mass of the monomer unit (147.17) is in good agreement with the spacing of the mass signals (AM = 146.93) of the most prominent peaks. Based on ear-... 

Theoretical calculations indicate that the CD of parallel and antiparallel (3-sheets are quite similar. This conclusion is supported by the CD spectrum of pelC,[1011021 a protein that has a parallel (3-helix motif, 1031 and therefore is more than 30% parallel (3-sheet with no antiparallel (3-sheet. Moreover, the parallel (3-sheet has a rather small degree of twist. The band positions and relative amplitudes in the CD spectrum of this protein resemble those for poly(Lys) in the (3-sheet form, which is an antiparallel sheet that is expected to be only slightly twisted because of the linear side chains. 

Roovers and Bywater 76 examined the temperature dependents of the electronic spectrum of poly(isoprenyi)iithium and were able to calculate an equilibrium constant for the dissociation event. On the basis that the process involved was tetramers dimers, the dissociation enthalpy was determined to be 12.3 kcal/mole in n-octane while a value of 9.0 kcal/mole was found in benzene solution. The latter value was thought to be due to weak solvations of the active centers by benzene. The approach used by Roovers and Bywater 76) is predicated on the assumption that the 272 and 320 nm absorptions represent species differing in their association state. 

Poly(2,5-silole) 7 shows a Aab of 482 nm at room temperature.24 A band gap of the polymer, if calculated with the absorption edge (650 nm), is 1.9 eV. A silole-thiophene alternating copolymer 8 can show a further decreased band gap.25 The copolymer displays a broad absorption spectrum with Aab at 648 nm in chloroform. The calculated band gap from the absorption edge is only 1.55 eV, a very small value so far reported for the synthesized SCPs. 

From the field desorption mass spectra of standard samples, a table for identification of poly(oxyethylene) alkylphenyl ethers and determination of the degree of polymerisation of ethylene oxide was constructed as shown in Table 6.1 n is the number of alkyl carbon atoms and m is the degree of polymerisation of ethylene oxide. When the field desorption mass spectrum having a peak pattern with the difference of 44m/z was obtained such as the peaks at 484, 528, 572, 616 and 660m/z, Table 6.1 would show that those peaks are due to poly(oxyethylene) nonylphenyl ethers with the degree of polymerisation of 6-10 of ethylene oxide. Table 6.2 also shows the identification of poly(oxyethylene) dialkylphenyl ethers and determination of the degree of polymerisation of ethylene oxide based on calculations of the molecular weight. 

Figure 11.3 13C-NMR spectrum of SBR including poly(ethylene glycol) as internal standard, observed at 75 MHz. The signals in the region A-I are used to calculate the integral intensity according to the equations (11.1) [18]...

Poly-L-glutamate in 100 percent a-helical form shows a trough in the ORD spectrum with [a]233 = -15,000° in the random-coil form, [a]233 = -1,000° (the subscript 233 refers to the wavelength of light used). Calculate the proportion of a helix in a protein for which [a]233 = -7,160°, assuming the presence of a-helical and disordered regions only. 

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