Ordered magnetic moment

Table 9. Conduction electron polarization effect in uranium ferromagnetic monocompounds conduction electron polarization moment Psai saturation moment from magnetization studies ordered magnetic moment as determined by neutron scattering...

For the optical activity of achiral chromophores with a dissymmetric environment, two types of theoretical treatments have been proposed coupled oscillator treatment and one-electron treatment. The charge distribution of the magnetic dipole transition correlates Coulombically with an electric dipole induced in the substituents, and the colinear component of the induced dipole provides, with the zero-th order magnetic moment, a non-vanishing rotational strength. 

The fact that the phase transition in UO2 has the first-order character and the ordered magnetic moment of 1.74 /ab is considerably lower than the paramagnetic moment (about 3 /ab) is qualitatively consistent with the ratio of the strength of the bilinear and biquadratic parts of the effective spin Hamiltonian (8) of the 5f2-5f2... 

Our spectroscopic study of the (ErxYi.x)2BaNiOs system (0.1wave functions, and g-factors of the Er3+ ion practically do not depend on x. It is physically reasonable to assume that the molecular-field constant X of the Er-Ni interaction also does not depend on x. In this case, Eqs. (2) and (3) are valid for an arbitrary x and the ordered magnetic moments of the Er and Ni magnetic subsystems can be extracted from the experimentally measured ground-state splittings. 

Figure 5. Temperature dependences of the ordered magnetic moments of nickel and erbium subsystems in Er2BaNi05 (open circles) calculated from the measured Er3+ ground-state splitting A(7) according to Eqs. (2) and (3) with mEr(0)=7.24 pB [7], A.=l.81 T/pB. Data from neutron scatterine measurements T9. 71 are also shown.

Figure 23 Magnetic structures of the phosphides AC02P2 (A = Ca, Sr, La, Ce, Pr, Nd, Eu). The cobalt atoms (small circles) with their ordered magnetic moments are shown together with the A atoms (large circles), which are in the positions tO 0 Ot ana n /o 1 ni n r tn body-centered nuclear cell (from Reehuis et ) o e...

In the ligand polarization mechanism for optical activity, the potential of the electric hexadecapole component, Hxy(x>-y>), produces a determinate correlation of the induced electric dipole moment in each ligand group which does not lie in an octahedral symmetry plane of the [Co Ng] chromophore (Fig. 8). The resultant first-order electric dipole transition moment has a non-vanishing component collinear with the zero-order magnetic moment of the dxy dxj yj transition in chiral complexes, and the scalar product of these two moments affords the z-component of the rotational strength, RJg, of the Aj -> Ti octahedral excitation. 

Most of the Mossbauer experiments on the actinides were performed with the 60 keV transition of 237 Np, which provides an extremely good resolution for hyperfine interactions. A comparison of the hyperfine fields (Hhl) at Np nuclei with the ordered magnetic moments (p) obtained from neutron diffraction data shows that there is a remarkably good correlation and a linear least-squares fit provides the relation (Dunlap and Kalvius 1985),... 

A singular compound in this group containing Sb is URuSb which is ferromagnetic below 35 K and possesses a low ordered magnetic moment, fi = 0.6pB (Palstra et al. 1987). 

Molecular field theory (MFT) is the simplest theory of ordered magnetic moments in solids. Proposed in 1907 by P. Weiss, its main assumption is... 

Regarding the very small ordered magnetic moment observed below the lower superconducting transition, one might think of four possibilities that are immediately at hand ... 

The ordered magnetic moment of the Sm ion is only 0.37(3)/tB, which is quite small compared to the heavy lanthanides. With the high ordering temperature of 6K, it is quite clear that the energetics must be dominated by exchange interactions, with the dipolar interactions playing only a very minor role. In the doped superconducting... 

We start with a calculation of the ordering temperature solely based on the dipolar interaction. According to calculations by Smit et al. (1987) the contributions to the dipolar fields due to adjacent R layers are insignificant hence, a 2D calculation is sufficient to obtain an idea of the importance of the dipolar interaction. For our cluster calculations (following the method described by Macisaac et al. 1992), we used the ordered magnetic moment obtained from neutron diffraction or - if no data were available - the value calculated from the CEF parameters. The size and direction of the moment together with the lattice constants used for our calculations are fisted in table 3. 

Po ordered magnetic moment determined in ME or ND experiments d electrons of the same spin on the same atom... 

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