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MoNiC

M. Motton, monic Polymerisation Principles and Practice, Academic Press, Inc., New York, 1982. [Pg.241]

If, in particular, we convert a matrix L —xl into its SCF, where now the (0,1)-entries of L are elements of -Fig], and factor the similarity invariants into products of powers of monic irreducible polynomials Pj x), so that fi x) =... [Pg.263]

Recalling that the companion matrix of any monic polynomial, e x)... [Pg.263]

Fig. 6. Vibrational states corresponding to axial H-atom vibrations (y-coordinate) and perpendicular B-atom vibrations (atj, x2 — coordinates) in the absence and presence of anhar-monic coupling (see text). For state mn,n2>, the m is the H-vibrational quantum number, and the n s are the B-vibrational quantum numbers. The infrared absorption corresponding to the m = 0 to m = 1 transition is sensitive to the B-isotope, as seen in the figure (solid vertical lines). Also, the transition n = 0 to n = 2 is now weakly allowed due to the mixing with the H-mode these two-phonon transitions are indicated by dashed vertical lines. Less important vibrational states are not shown on the figure. Fig. 6. Vibrational states corresponding to axial H-atom vibrations (y-coordinate) and perpendicular B-atom vibrations (atj, x2 — coordinates) in the absence and presence of anhar-monic coupling (see text). For state mn,n2>, the m is the H-vibrational quantum number, and the n s are the B-vibrational quantum numbers. The infrared absorption corresponding to the m = 0 to m = 1 transition is sensitive to the B-isotope, as seen in the figure (solid vertical lines). Also, the transition n = 0 to n = 2 is now weakly allowed due to the mixing with the H-mode these two-phonon transitions are indicated by dashed vertical lines. Less important vibrational states are not shown on the figure.
In the course of the total synthesis of pseudo-monic add C analogues a novel domino ene reaction is employed by Marko et al (scheme 21).[601 This methodology consists of an ene-reaction which is followed by a concomitant intramolecular silyl-mediated Sakurai (ISMS) cydization. Using two equivalents of the same aldehyde the readion proceeds in the presence of BF3 OEt2. However, the syn-... [Pg.53]

The prerequisites for high accuracy are coupled-cluster calculations with the inclusion of connected triples [e.g., CCSD(T)], either in conjunction with R12 theory or with correlation-consistent basis sets of at least quadruple-zeta quality followed by extrapolation. In addition, harmonic vibrational corrections must always be included. For small molecules, such as those contained in Table 1.11, such calculations have errors of the order of a few kJ/mol. To reduce the error below 1 kJ/mol, connected quadruples must be taken into account, together with anhar-monic vibrational and first-order relativistic corrections. In practice, the approximate treatment of connected triples in the CCSD(T) model introduces an error (relative to CCSDT) that often tends to cancel the... [Pg.26]

Herzberg uses v and oo to symbolize observed (anhar-monic) and harmonic vibrational frequencies, respectively. [Pg.116]

This is not twice the fundamental frequency, but is lower than this, due to the increased effect of the anhar-monicity constant in transitions to higher values of n. [Pg.114]

Sbmation.—1. By the action of heat upon the neutral am monic salts of dibasic acids —... [Pg.374]

This parameter is referred to as revival time [37, 44]. In general, the anhar-monicity is small enough for 7]. to be much larger than T vib- Figure 7.1 shows an example of simulated WP motion in an anharmonic potential, where 300 fs and Tjgy 37 ps. [Pg.286]

Just above the saddle energy, the quantization can be performed by the usual perturbation theory applied to scattering systems as described by Miller and Seideman [24], This equilibrium point quantization uses Dunham expansions of the form (2.8) with imaginary coefficients. This method is valid for relatively low-lying resonances above the saddle, up to the point where anhar-monicities become so important that the Dunham expansion is no longer applicable (see the discussion in Section II.B). [Pg.555]

The derivation of (4.13) shows that the equilibrium point quantization and the periodic-orbit quantization can be compared term by term. This comparison shows that the periodic-orbit quantization is able to take into account the anharmonicities in the direction of symmetric stretch. However, the anhar-monicities are neglected in the other directions transverse to the periodic orbit. Their full treatment requires the calculation of h corrections to the Gutzwiller trace formula, as shown elsewhere [14]. [Pg.556]

For systems where there is variable spacing between absorption bands, it would, of course, be necessary to include anhar-monicity corrections. [Pg.133]

White and coworkers used trans Addition of bromine and (-)-l-bomeol to 3,4-dihydro-2//-pyran to afford the stereoisomeric bomyl bromotetrahydropyranyl ethers (3) and (4 Scheme 44) which are employed in an enantioselective total synthesis of (-)-monic acid C (Scheme 5).10 A simple synthesis of 4-methylthio-l,2-dithiolane, the photosynthesis inhibitor of the green alga Chara globularis (Scheme 45),83 exploits the observation that allylic sulfides undergo rearrangement on addition of bromine.84 Block and Naganathan employed the trans addition of bromine to 4-thioacetoxycyclopentene as a key... [Pg.345]


See other pages where MoNiC is mentioned: [Pg.456]    [Pg.127]    [Pg.243]    [Pg.44]    [Pg.400]    [Pg.37]    [Pg.189]    [Pg.263]    [Pg.63]    [Pg.98]    [Pg.363]    [Pg.92]    [Pg.302]    [Pg.211]    [Pg.252]    [Pg.45]    [Pg.160]    [Pg.126]    [Pg.134]    [Pg.76]    [Pg.155]    [Pg.266]    [Pg.284]    [Pg.294]    [Pg.938]    [Pg.20]    [Pg.590]    [Pg.832]    [Pg.382]    [Pg.386]    [Pg.226]    [Pg.331]    [Pg.332]   
See also in sourсe #XX -- [ Pg.2 , Pg.2 , Pg.24 , Pg.48 ]




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