Pseudo-doublet

The same proton is irradiated, and just as in the difference experiment, one aromatic pseudo-doublet shows a strong NOE a very weak but just visible effect is shown by the OCH2 protons. 

Figure 1.4 Plot of the lowest hyperfine split pseudo-doublet for field applied along the easy magnetization axis of Na9Ho(W5018)2 t)H20. Grey dotted lines are obtained in the assumption of purely axial symmetry while black continuous lines result after inclusion...

Normal quartet Inside out quartet Pseudo-doublet... 

For 4Jp + 2Jf = 0, the matrix splits into two separate 2x2 blocks, which have the same eigenvalues. The splitting pattern is thus as in the central panel of Fig. 7.5. Such a case can occur for a state. The orbital part of this state has no angular momentum, since the corresponding operator is not included in the direct square Ti E x E. As result, the magnetic moment of such a state is due only to the doublet spin part. Such a state behaves as a pseudo-doublet. 

A rare example of a mononuclear Ir hydride complex bearing an ortho-metalated phosphine ligand, [Ir(H)(K P,P,P,P,C-l)]PF6, has been obtained by Gloaguen et by coordination of tris((2-diphenylphos-phino)ben l)-phosphine to the cationic Ir(i) precursor [Ir(COE)2(aceto-ne)2]PFe, where COE = cyclooctene. A complex hydride signal observed in the H NMR spectrum of this compound at 6 —5.9 ppm was resolved as a pseudo doublet of quartets with one large H-P coupling, /hp = 115.4 Hz trans) and a much smaller coupling, /hp = 10.8 Hz (c/s). The NMR spectrum revealed a doublet at 120.6 ppm, with a /cp value of 41.6 Hz, indicative of a direct Ir-carbon bond. 

With all semi-empirical methods, HyperChem can also perform pseudo-RHF calculations for open-shell systems. For a doublet state, all electrons except one are paired. The electron is formally divided into two half electrons with paired spins. Each half elec-... 

As mentioned earlier, rare-earth zircons are ideal cases for the study of CJTE. In TmV04, at high temperatures, the lowest electronic state of Tm ion is an E doublet. A pseudo-JT effect occurs if there is accidental or near degeneracy. DyVO is such an example where two Kramers doublets are separated by 9cm another example is TbV04. The rather unusual features of the low-lying electronic states of rare-earth... 

It was found possible to measure the kinetics of cleavage of protonated sec-butyl methyl ether 24 by following the disappearance of the methoxy doublet in the NMR spectrum with simultaneous formation of protonated methanol and ferf-butyl cation. The cleavage shows pseudo-first-order kinetics. Presumably, the rate-determining step is the formation of sec-butyl cation followed by rapid rearrangement to the more stable ferf-butyl cation... 

Fig. 2. Correlation diagram of the doublet states between weak (left) and strong (right) spin-orbit coupling. In the strong coupling limit the splitting pattern is determined by the pseudo-./ quantum number...

Photophyskal Steps. The energy levels and spectra of these complexes have been described [13,28-30]. The ground, lowest quartet, and lowest doublet states are designated in Figure 1 with the pseudo-octahedral symbols. Excitation to T2 or to a higher quartet state is followed by rapid vibrational deactivation to the thermalized T2 or prompt intersystem crossing to the doublet manifold. With rare exceptions, E is below T2 and the emission is a narrow E => A2 spectrum. 

In addition to the 72 and states, the T, state lies some 500cm above in pseudo-octahedral complexes. In lower symmetry complexes both E and Tj are split, and in strong tetragonal fields, one of the Tj components is below E [32] as evidenced by the markedly broader emission spectrum [33]. There appears to be good thermalization between the Ti and E states. As a result of the thermalization, all of the photophysical rates for steps originating in E/ T, are population weighted averages of the rate constants for the individual states. If all reaction occurs in doublet states, the same conclusion applies to calculated from Eq. (21). 

Figure. 12. PES slices (radial potentials) Vj(R, y 0) energies are given inkcal/mol left panel 18 doublet PES s calculated with the contribution of S-O interaction are ascribed to 4 uncoupled groups of 1, 3, 6, 8 states with Mj =7/2, 5/2, 3/2, 1/2 shown with dash-dotted, dotted, dashed, and solid curves respectively free-fragment correlations are assigned for the example of triple pseudo-crossing in the group of 8 states with Mj =l/2 right panel 8 PES s calculated without contribution of the S-O interaction are ascribed to irreducible representations ( X + Z + rt-+- A) of the symmetry group C v-...

For non-Kramers levels (integral pseudo-spin) k(oo0) goes as w0 2, while for a Kramers doublet (spin states j) the coupling is a combined effect of strain and of... 

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