Electric axis orientated

Figure 6. Orientation of magnetic field, electric axis, and rotation axes in Al(III)...

Fig. 6.5. (a) Angular momentum orientation via beam deflection in a magnetic field. (6) Figure axis orientation for symmetric top molecules via beam deflection in an electric field, (c) Figure axis orientation in hexapole focussing field. 

Figure 1. Schematic diagrams of TEB and LLS instrumentation. P, pinholes L, lenses B, polarizers C, cell Q, quarter wave plate PMT, photomultiplier tube HVG, high voltage generator MP, microprocessor TR, transient recorder CL, correlator CT, counter 6, scattering angle. For the TEB setup polarizers B-, B2 have polarization axis oriented at tt/4 with respect to the x-axis, as shown in (a). After the light beam passed through the cell with electric field in the x-direction containing a suspension of anisotropic particles and the quarter waveplate with its fast axis oriented at tt/4 with respect to the x-axis, the transmitted light beam is polarized in the direction of 71/4 + 6/2, as shown in (b). Analyzer B has polarization axis oriented at 3t/4 + a as shown in (c).

The 90 geometry of Figure 6.25 does not require a polarizer to determine p but does require rotation of the laser polarization. The intensity (/j) is determined with the laser electric field oriented on the y axis, with the observation axis along the x axis. Then the laser electric field is rotated 90 (usually with a quarter wave plate) to position it parallel to the x axis. The observed intensity is now /x, and p may be calculated directly from the two spectra. 

Mossbauer spectroscopy is also able to give local moment orientations, with respect to the crystalline lattice, or the correlations between moment orientations and local distortion axis orientations in a chemically disordered or amorphous material. This arises from the interplay between the structural (electric field gradient) hyperfine parameters and the magnetic hyperfine parameters. In this way, the spin flop Morin transition of hematite, for example, is easily detected and characterized (e.g., Dang et al. 1998). The noncollinear magnetic structures of nanoparticles can also be characterized. 

In the linear-response range, a time-dependent electric field oriented along the axis ... 

We consider first the OS of the donor electron transitions corresponding to a single valley. With the axis orientation used in Hamiltonian (5.5), the matrix elements for transitions from the Is state to odd-parity states with m = 0 are non-zero when the electric vector (polarization vector) of the radiation is parallel to the z axis similarly those for transitions from the Is state to odd-parity states with m = 1 are non-zero when the electric vector is perpendicular to the 2 axis. The one-valley OSs are denoted accordingly as /// and / i. When considering the multi-valley degeneracy, it can be shown that for an arbitrary choice of the polarization vector, the OS for transitions from the Is (Ai) ground state to the odd-parity states with m = 0 is /o = fjj and those for transitions from the Is (Ai) ground state to the odd-parity states... 

In cylindrical system of coordinates with the z-axis oriented along the borehole axis and the dipole located in its origin the electric field has only one component E, but the magnetic field has two components, Hr and 77. On the borehole axis the electrical field, E, and the component of the magnetic field. Hr, are both equal to zero. In other words, the magnetic field is directed along the borehole axis. 

When a discotic liquid crystal is sandwiched between two substrates (or exposed to air), the direction of the uniaxial axis can be controlled by alignment layers, external electric fields, and chiral dopants [46,47]. It is therefore possible to develop discotic compensation films with spatially varied uniaxial axis orientations. For example, Fuji Photo Film Co. developed discotic compensation films for TN LCDs. In both the TN display and discotic compensation film, the liquid crystal directors vary in the vertical direction. Each layer of nematic liquid crystal with a certain director orientation is compensated by a layer of discotic liquid crystal with the same director orientation. 

Fig. 3.1 Contour plots of the electric potaitial generated an electric dipole oriented along the z axis, as functions of position in the yz plane. The dipole consists of a unit positive charge at (y, z) = (0, ri2/2) and a unit negative charge at (0, —ri2/2). Solid lines represent positive potentials dotted lines, negative potentials. The contour intervals are 0.2 e/ri2 in A and 0.001 ejd 2 in B lines for Weiec > 4e/fi2 are omitted for clarity. The electric field vectors (not shown) are oriented normal to the contour lines of the potential, pointing in the direction of more positive potential. Their magnitudes are inversely proportional to the distances between the contour lines...

As shown below, the assignment of the ZFS-parameters to the molecular axis can be made very easily by using liquid crystals as host to orient the triplet molecules. Since esr-spectra of excited triplet states can only be observed in rigid solvents ordered glasses are needed for such experiments. As noted in Section 1 uniaxial glasses can easily be prepared from the electric field oriented nematic mixtures of cholesteryl derivatives. 

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