Azimuthal

Azimuthal resistivity (depth of investigation Gamma ray 12in. orless) detector... 

This region has been divided into two subphases, L and S. The L phase differs from the L2 phase in the direction of tilt. Molecules tilt toward their nearest neighbors in L2 and toward next nearest neighbors in L (a smectic F phase). The S phase comprises the higher-ir and lower-T part of L2. This phase is characterized by smectic H or a tilted herringbone structure and there are two molecules (of different orientation) in the unit cell. Another phase having a different tilt direction, L, can appear between the L2 and L 2 phases. A new phase has been identified in the L 2 domain. It is probably a smectic L structure of different azimuthal tilt than L2 [185]. 

APD, ARPEFS Azimuthal PED, angle- Same as PED resolved photoemission extended fine structure Spectroscopy of Emitted X-rays or Photons Same as PED... 

The wavevector is a good quantum number e.g., the orbitals of the Kohn-Sham equations [21] can be rigorously labelled by k and spin. In tln-ee dimensions, four quantum numbers are required to characterize an eigenstate. In spherically syimnetric atoms, the numbers correspond to n, /, m., s, the principal, angular momentum, azimuthal and spin quantum numbers, respectively. Bloch s theorem states that the equivalent... 

Consider the case of two neutral, linear, dipolar molecules, such as HCN and KCl, in a coordinate system with its origin at the CM of molecule A and the z-axis aligned with the intemiolecular vector r pointing from the CM of A to the CM of B. The relative orientation of the two molecules is uniquely specified by their spherical polar angles 0, 03 and the difierence <]) = - <])3 between their azimuthal angles. The leading temi in the... 

The ESDIAD pattern does, however, provide very usefril infomiation on the nature and synnnetry of an adsorbate. As an example, figure A1.7.13(a) shows the ESDIAD pattern of desorbed collected from a 0.25 ML coverage of PF on Ru(OOOl) [89]. The pattern displays a ring of emission, which indicates that the molecule adsorbs intact and is bonded tlirough the P end. It freely rotates about the P-Ru bond so that tlie emission occurs at all azimuthal angles, regardless of the substrate structure. In figure A1.7.13(b), the... 

Figure A3.1.7. Direct and restituting collisions in the relative coordinate frame. The collision cylinders as well as the appropriate scattering and azimuthal angles are illustrated.

Thus die increase of particles in our region due to restituting collisions with an impact parameter between b and b + Ab and azimuthal angle between e and e + de (see figure A3.1.7 can be obtained by adjusting the expression for the decrease of particles due to a small collision cylinder ... 

The primes and subscripts on the /s refer to their velocity arguments, and the primed velocities in the gain tenn should be regarded as fiinctions of the imprimed quantities according to (A3.1.36). It is often convenient to rewrite the integral over the impact parameter and the azimuthal angle as an integral over the unit vector kas... 

Note that for potentials that depend only on the scalar distance r between the colliding particles, the amplitude y (9) does not depend on the azimuthal angle associated with the direction of observation. 

Frederick B G, Power J R, Cole R J, Perry C C, Chen Q, Flaq S, Bertrams T, Richardson N V and Weightman P 1998 Adsorbate azimuthal orientation from reflectance anisotropy spectroscopy P/rys. Rev. Lett. 80 4490-3... 

Figure Bl.23.8. Scattering intensity of 2 keV Ne versus azimuthal angle 6 scans for Pt 110] in the (1 x 2) and (1 X 3) reconstructed phases. Scattering angle 0 = 28° and incident angle a = 6°.

Azimuthal scans obtained for tliree surface phases of Ni l 10] are shown in figure B 1.23.9 [38]. The minima observed for the clean and hydrogen-covered surfaces are due only to Ni atoms shadowing neighbouring Ni atoms, whereas for the oxygen-covered surface minima are observed due to both O and Ni atoms shadowing... 

Figure Bl.23.9. Scattering intensity of 4 keV Ne versus azimuthal angle 8 for a Ni 110] surface in the clean (1 X 1), (1 X 2)-H missing row, and (2 x l)-0 missing row phases. The hydrogen atoms are not shown. The oxygen atoms are shown as small open circles. 0-Ni and Ni-Ni denote the directions along which O and Ni atoms, respectively, shadow the Ni scattering centre.

Figure Bl.23.13. A series of 20 time-resolved SARIS frames for 4 keV He seattering from Pt 111 ] -(1 x 2) taken every 3° of rotation about the azimuthal angle 5, starting with = 0° as the (M1) azimuth and 60° as the (112) azimuth. Eaeh frame represents a 16.7 ns window eentred at the TOF eorresponding to QSS as predieted by the BCA. The abseissa is the erystal azimuthal angle (5) and the ordinate is tire partiele exit angle...

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