Magnetic schematic densities

Figure 19.4 (a) Schematic densities of states N ) for a concentrated magnetic semiconductor... 

Fig. 2.9. General schematic of a sector mass analyzer. Ions extracted from the ion source are accelerated by an electrostatic field (accelerating potential, 10 and enter the sector analyzer with velocity, v. Electric (electric flux density, E) or magnetic (magnetic flux density, 6) fields bend the trajectory of the ions into curved paths with radius, r. Trajectories of ions with larger m/z are affected more than smaller ones. An illustration of the direction-focusing ion beam approach in a magnetic sector mass analyzer is shown in the insert. Due to the dependence of the radius of an ion s trajectory on its kinetic energy ( ) in the electrostatic sector mass analyzer and on its momentum (mv) in the magnetic sector mass analyzer, the systems are also referred to as ion energy and ion momentum filters.

Figure 4 schematically shows a typical field cyde. The external magnetic flux density is cycled in a sequence of three different values the polarization field, the relaxation field, and the detection field. The sample is polarized in the polarization field. Bp, which is chosen as high as compatible with the cooling device of the resistive magnet coil [21]. This takes a couple of spin-lattice relaxation times taken at this particular field value. After that the magnetization is equal to the Curie equilibrium magnetization Mo(Bp). 

For our purpose, it is convenient to classify the measurements according to the format of the data produced. Sensors provide scalar valued quantities of the bulk fluid i. e. density p(t), refractive index n(t), viscosity dielectric constant e(t) and speed of sound Vj(t). Spectrometers provide vector valued quantities of the bulk fluid. Good examples include absorption spectra A t) associated with (1) far-, mid- and near-infrared FIR, MIR, NIR, (2) ultraviolet and visible UV-VIS, (3) nuclear magnetic resonance NMR, (4) electron paramagnetic resonance EPR, (5) vibrational circular dichroism VCD and (6) electronic circular dichroism ECD. Vector valued quantities are also obtained from fluorescence I t) and the Raman effect /(t). Some spectrometers produce matrix valued quantities M(t) of the bulk fluid. Here 2D-NMR spectra, 2D-EPR and 2D-flourescence spectra are noteworthy. A schematic representation of a very general experimental configuration is shown in Figure 4.1 where r is the recycle time for the system. 

Fig. 14. Schematic design of the Cerex probe. This is a sensor for optical density and mounted vertically in situ. Suspension enters the side drain ports deliberately and can be trapped inside the sensor by powering the solenoid coils the magnetic plunger closes the side ports. In the meantime, the trapped dispersion degasses and bubbles disappear through the upper vent hole. After some time, the optical density reading is declared representative . The next cycle starts with opening the side drain ports...

Figure 2 Schematic description of some 57 Fe Mossbauer spectra showing original nuclear energy levels (A) slightly perturbed through interaction with S electron density (B) giving rise to a chemical shift (8) resulting from quadrupole interactions (C) and magnetic splitting of the ground and excited states (D). Arrows indicate transitions responsible for one,...

Fig. 13 Schematic ground-state phase diagram for the spin-1/2 XXZ model in the magnetic field in one [115] and two dimensions [119]. The line of A = 0 corresponds to the half-filling in the Holstein model. Antiferromagnetic, ferromagnetic, and XY phases correspond, respectively, to charge density wave, band insulating, and superconducting states in the Holstein model...

The power available within a molecular system to induce transitions by virtue of its molecular tumbling is referred to as the spectral density J(co) (Section 2.5) and this provides a measure of how the relaxation rates Wq, W] and W2 vary as a function of tumbling rates. This is illustrated schematically in Fig. 8.6 for three different correlation times. An alternative description of the spectral density is that it represents the probability of finding a fluctuating magnetic component at any given frequency as a result of the motion and as such the area under each of the curves of Fig. 8.6 must then be equal. Thus, for a molecule with a short tc (rapid tumbling) there exists an almost... 

Fig. 4a-c. Schematic representation of the overlap density in three cases of strict orthogonality of the magnetic orbitals, leading to a weak (a), intermediate (b) and strong (c) ferromagnetic interaction... 

The interacting magnetic orbitals in [CuFe] (hence also in [CuCr]) are schematized in the first and third columns of Fig. 11 and the overlap densities between pairs of magnetic orbitals in the second column. pb a, is an overlap density of the same nature as that... 

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