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Complex polarization propagator

As was the case for the absorption spectrum, different calculations of the band MCD of ZnP and MgP have produced different interpretations of the observed spectral features. Solheim et al. have recently calculated the MCD spectra of ZnP, MgP, and NiP using their complex polarization propagator method and a hybrid... [Pg.90]

The complex polarization propagator method has been applied to the calculations of dipole-dipole dispersion coefficients of pyridine, pyrazine, and r-tetrazine. These calculations refer to the electronic ground states as well as the first excited states of 7t—>7t character <2004MI321>. Calculations of static and dynamic polarizabilities of excited states by means of DFT have been performed <2004JCP9795>. [Pg.644]

Alternatively, one can generate the absorption spectrum using complex polarization propagator/damped response approaches. Implementations of the CPP/DRT exist at the HF and TD-DFT levels of theory [35, 43]. [Pg.108]

In a recent experimental study of the ethylene MCD spectrum (Snyder et al. 2004), the assignment of the transitions was revised. The proposed new assignment is in agreement with earher ab initio calculations of the B term in ethylene (Coriani et al. 1999b). Recently, also calculations of the A term of magnetic circular dichroism appeared (Seth et al. 2004). We also note that both the A and B terms come out directly from calculations using the complex polarization propagator approach (SoUieim et al. 2008). [Pg.410]

Solheim, H.> Ruud, K.> Coriani, S.> 8c Norman, P. (2008). Complex polarization propagator calculations of magnetic circular dichroism spectra. Journal of Chemical Physics, 128, 094103. [Pg.440]

Villaume S, Saue T, Norman P. Linear complex polarization propagator in a four-component Kohn-Sham framework. J Chem Phys. 2010 133 064105. [Pg.295]

Linares M, Stafstrom S, Rinkevicius Z, Agren H, Norman P. Complex Polarization Propagator Approach in the Restricted Open-Shell, Self-Consistent Field Approximation The Near K-Edge X-ray Absorption Fine Structure Spectra of Allyl and Copper Phthalocyanine. J Phys Chem B. 2010 115 5096-5102. [Pg.295]

There are few studies of the effect of temperature on monomer reactivity ratios [Morton, 1983]. For styrene-1,3-butadiene copolymerization by r-butyllithium in rc-hexane, there is negligible change in r values with temperature with r — 0.03, r2 = 13.3 at 0°C and n = 0.04, r% = 11.8 at 50°C. There is, however, a signihcant effect of temperature for copolymerization in tetrahydrofuran with r — 11.0, r2 = 0.04 at —78°C and r — 4.00, r2 = 0.30 at 25° C. The difference between copolymerization in polar and nonpolar solvents is attributed to preferential complexing of propagating centers and counterion by 1,3-butadiene as described previously. The change in r values in polar solvent is attributed to the same phenomenon. The extent of solvation decreases with increasing temperature, and this results in... [Pg.512]

The above comprises the derivation of the expression for the PES of the complex system which is not only free from the necessity to recalculate the wave function of the classical subsystem in each point, but formally not requiring any wave function of the M-system at all, since the result is expressed in terms of the generalized observables - one-electron Green s functions and the polarization propagator of the free M-system. Reality is of course more harsh as the necessary quantities must be known for a system we know too little about, except the initial assumption that its orbitals do exist. Section 3.5 will be devoted to reducing this uncertainty. [Pg.89]

The expression for the cubic response function is given in Eq. (2.60) of Olsen and Jorgensen (1985). All the propagators that are derived from response theory are retarded polarization propagators. The poles are placed in the lower complex plane. This is specified through the energy variables Ei+itj and 2 + ii . The Pjj operator in Eq. (35) permutes Ei and 2 and it is assumed that the - 0 limit must be taken of the response functions. [Pg.208]

J.E. Del Bene, I. Alkorta, I.J. Elguero, A systematic comparison of second-order polarization propagator approximation (SOPPA) and equation-of-motion coupled cluster singes and doubles (EOM — CCSD) spin — spin couphng constants for selected singly bonded molecules, and the hydrides NH3, H2O, and HF and their protonated and deprotonated ions and hydrogen-bonded complexes, J. Chem. Theor. Comput. 4 (2008) 967-973. [Pg.223]

Relativistic calculations of NMR properties of RgH ion (where Rg = Ne, Ar, Kr, Xe), Pt shielding in platinum complexes, and Pb shielding in solid ionic lead(II) halides have been reported in this review period. For the Rg nucleus in the RgH ions, the following methods were used and results compared with each other non-relativistic uncorrelated method (HF), relativistic uncorrelated methods, four component Dirac Hartree-Fock method (DHF) and two-component zeroth order regular approach (ZORA), non-relativistic correlated methods using second order polarization propagator approach SOPPA(CCSD), SOPPA(MP2), respectively coupled cluster singles and doubles or second order Moller-Plesset, and... [Pg.66]

It was possible to formulate a rule describing how the copolymerization parameters depend on the polarity of the solvent used. This rule is a result of contemplation about the connection between the copolymerization parameters and propagation rate constants during the cationic polymerization as well as about the changes of solvation of educts and activated complexes of the crossed propagation steps in solvents with varied polarity 14 U7). The rule is as follows ... [Pg.222]

The authors concluded that the side reactions normally observed in amine-initiated NCA polymerizations are simply a consequence of impurities. Since the main side reactions in these polymerizations do not involve reaction with adventitious impurities such as water, but instead reactions with monomer, solvent, or polymer (i.e., termination by reaction of the amine-end with an ester side chain, attack of DMF by the amine-end, or chain transfer to monomer) [11, 12], this conclusion does not seem to be well justified. It is likely that the role of impurities (e.g., water) in these polymerizations is very complex. A possible explanation for the polymerization control observed under high vacuum is that the impurities act to catalyze side reactions with monomer, polymer, or solvent. In this scenario, it is reasonable to speculate that polar species such as water can bind to monomers or the propagating chain-end and thus influence their reactivity. [Pg.9]

Since the solvents used (e.g., chlorinated hydrocarbons, benzene, THF) are only mildly polar, the negative counter-ion will be held near the propagating carbenium ion center. Highly polar solvents are not generally useful since they either react with and destroy the initiator and propagating centers or deactivate them by strong complexation. [Pg.16]

This is indeed a system of three second-order differential equations. The tensor elements Cyki may be complex-valued in case of viscoelasticity. Analysis shows that the propagation can be split into three orthogonally polarized planar waves propagating along a wave vector k. Those three waves may have different propagating celerities. Phase celerity and polarization ilj are connected through Christoffel equation ... [Pg.214]


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See also in sourсe #XX -- [ Pg.86 , Pg.112 , Pg.144 ]




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