Hyperfme coupling constants

Hence, a measurement of hyperfme coupling constants provides infonnation on spin densities at certain positions in the molecule and thus renders a map of tlie electronic wavefiinction. 

As for CIDNP, the polarization pattern is multiplet (E/A or A/E) for each radical if Ag is smaller than the hyperfme coupling constants. In the case where Ag is large compared with the hyperfmes, net polarization (one radical A and the other E or vice versa) is observed. A set of mles similar to those for CIDNP have been developed for both multiplet and net RPM in CIDEP (equation (B1.16.8) and equation (B1.16.9)) [36]. In both expressions, p is postitive for triplet precursors and negative for singlet precursors. J is always negative for neutral RPs, but there is evidence for positive J values in radical ion reactions [37]. In equation (B 1.16.8),... 

Table 6. Comparison of the Isotropic Hyperfme Coupling Constants for the Flavosemiquinones...

Ring Position Hyperfme coupling constants in Gauss ... 

TABLE 9. Isotropic hyperfme coupling constants (Aiso) for ScC02 and OScCO lowest isomers... 

Munzarova, M., Kaupp, M., 1999, A Critical Validation of Density Functional and Coupled Cluster Approaches for the Calculation for EPR Hyperfme Coupling Constants in Transition Metal Complexes , J. Phys. Chem. A, 103, 9966. 

Although the switching of exchange interaction was detected by a susceptibility measurement of biradical 10, both open- and closed-ring isomers 10a and 10b had nine-line ESR spectra because the exchange interaction between the two radicals was much stronger than the hyperfme coupling constant in both isomers. For one... 

The signs and amplitudes of nuclear polarizations depend on chemical parameters and on the hyperfme coupling constants and g factors of the free radicals involved in the reactions. If the chemical parameters are known, the radi-... 

The triplet of frequencies gives rise to a beating in the time-domain spectrum as seen for a powder sample of ZnO in Figure 1. The separation of the two satellite lines provides a direct measure of the hyperfme coupling constant between the muon and the electron. This is 500 20 kHz, which is 0.011% of the free-muonium value of 4463 MHz, indicating immediately a small electron spin density at the site of the muon and an extended waveflmction associated with a shallow donor state. 

Calculated(60) and experimental(P2) isotropic hyperfme coupling constants and spin densities for the menasemiquinone radical anion(MQ )- Calculations were done by using the... 

Isotropic hyperfme coupling constants have also been calculated for UQ and are summarized in Table 12.(5S) The table shows good agreement between... 

A, (1) mass number of a nucleus (2) net CIDNP absorption a, hyperfme coupling constant in an EPR spectrum... 

Here a(T) expresses an enhancement factor due to an electron correlation effect. We neglect the temperature dependence of a(T) for the present. A is the hyperfme coupling constant when the S function interaction is assumed. In the case when the transferred hyperfine coupling depends on the neighbouring spins, A is no longer constant but wavenumber dependent as will be mentioned later. E and/(E) are the energy of the quasiparticles and the Fermi function, respectively. The density of states of the quasiparticles NS(E) and the anomalous density of states MS(E) associated with the coherent effect are expressed as follows ... 

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