Magnetic powder sample

From (4.56) and Table 4.3, we derive the relative intensity ratios 3 2 1 1 2 3 for the hyperfine components of a Zeeman pattern of a powder sample. The transition probability for the case of the polar angle 6 = Oq can readly be calculated by integrating (4.56) only over the azimuthal angle (j). One obtains a factor (1 + cos 0o)/2 and sin 0o for m = 1 and m = 0, respectively, which are multiplied by the square of the Clebsch-Gordan coefficients. As a consequence of the angular correlation of the transition probabilities the second and fifth hyperfine components (Fig. 4.17) disappear if the direction k of the y-rays and the magnetic field H are parallel (0q = 0). 

Fig. 4.17 Magnetic hyperfine pattern of a powder sample with randomly distributed internal magnetic field (a), and with (b) an applied magnetic field (0q = 90°), and (c) an applied magnetic field (00 = 0°)...

Fig. 7.3 Effect of magnetic dipole interaction (7/m), electric quadmpole interaction (Hq), and combined interaction// = Hu + //q, Em> q on the Mossbauernuclear levels of Ni. The larger spacings between the sublevels of the ground state are due to the somewhat larger magnetic dipole moment of the nuclear ground state as compared to the excited state. The relative transition probabilities for a powder sample as well as the relative positions of the transition lines are indicated by the stick spectra below...

Figure 8 Polar plots of the in-phase and quadrature components of the 79Br NMR signal in a powder sample of KBr in a magnetic field of 7 T under MAS at 5.1 kHz. The carrier frequencies were (A) 100.280545 MHz, (B) 100.281545 MHz, (C) 100.282545 MHz, and (D) 100.283545 MHz. The 79Br resonance frequency was 100.282545 MHz.

Figure 5.7 Magnetization (a) and susceptibility (b) of the Dy3 complex obtained on oriented single crystals and powdered samples. The Z direction is orthogonal to the Dy3 plane. The inset in the left panel shows the difference between the X and...

Figure 5.8 Static magnetic data for the Er(trensal) complex in the case of a powdered sample and an oriented single crystal measured in parallel or perpendicular direction to the C3 rotation axis, (a) Temperature dependence of the magnetic susceptibility...

Figure 10.4 Magnetic hysteresis curve recorded on a powder sample of 10 at 1.8 K. (Reprinted from Ref. [9], Copyright (2011) Wiley-VCH.)...

The complications that arise in solid state NMR spectra as compared to NMR spectra in solution are the consequence of the fixed orientation of the sample relative to the external magnetic field Bq. Mainly three interactions are responsible for the enormous linebroadening that can be observed for solid powder samples. These are (1) the shielding or chemical shift, including the chemical shift or shielding anisotropy CSA or Acr Hqsa) (2) homo- and/or heteronuclear dipole-dipole coupling (ffoo) and (3) in addition, for nuclei with spin >1/2, the quadrupolar interactions (Hq). 

Table 20. Magnetic properties of TI13P4 type compounds (° measured with a powder sample)... 

Figure 4. The eight-pulse line shape and the peak locations of the Th4Hi5 (LP) powder sample as a function of temperature using a Ca(OH)2 single crystal as reference. The reference is oriented such that the major principal axis of the proton chemical shift tensor is parallel to the external magnetic field. A shift to the left signifies an increase in the value of

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