Raleigh scatter

ELSD Evaporative light scattering detector Raleigh scattering of atomised eluent... 

The first term on the right corresponds to Raleigh scattering. The second term suggests an energy-exchange interaction that depends on the anisotropy of the polarizability and involves frequencies shifted from that of the incident radiation by an amount which depends on twice the rotational or vibrational frequency of the molecules in the sample. 

The selection rule for rotational Raman transitions are AJ = 2. This result relates to the involvement of two photons, each with angular momentum h, in the scattering process. Also allowed is A J = 0, but since such a transition implies zero change in energy it represents Raleigh scattering only. 

Figure 15.5 Schematic of instrumental apparatus. The DT/MH-functionalized AgFON was surgically implanted into a rat with an optical window and integrated into a conventional laboratory Raman spectroscopy system. The Raman spectroscopy system consists of a Ti sapphire laser (Acx = 785 nm), band-pass filter, beam-steering optics, collection optics, and a long-pass filterto reject Raleigh scattered light. All of the optics fit on a 4 ft x 10 ft optical table.

This theory is still relevant today, alongside Raleigh scattering theory, to describe the colors of our sky, as well as the appearance of suspensions such as milk and latex paints. It should be noted that for nonspherical nanostructures, the denominator of the bracketed term above is replaced with ... 

With respect to conventional fiber, the potential benefits of a hollow-core photonic crystal fiber are lower transmission losses (due to both reduced absorption and Raleigh scattering) and lower nonlinearities, since the core is air. In only a few years of research, interest in this area has led to remarkably low-loss fibers (13 dB/km at 1500 mn 100 m length)." With continued advances toward lower-loss photonic crystal fibers, efforts also have begun to address field-level issues, including microbend losses" " and fiber splicing." ... 

Finally, the instrumentation required for SE(R)RS measurements is not necessarily large or complex. Indeed, commercial, handheld spectrometers are available. In essence the technique requires a laser for excitation of the surface, a filter (notch or edge) to exclude the Raleigh-scattered radiation, a monochromator, and a detector to collect the Raman-scattered tight [19, 20, 23]. 

Dipole moment and Kerr effect measurements are frequently used for conformational analyses, e,g., the recent studies of the phosphepanes (88) and 1,3,2,5-dioxasilaphosphorinanes (89). On the other hand the anisotropy of polarization and conformational analysis of triphenylphosphine, trimesityl-phosphine, and their chalcogenides also incorporated Raleigh scattering measurements (c/. ref. 236), whilst conformation studies of 1,3,5-dioxaphosphorinanes combined dipole moments with n.m.r. or u.v. data or reactive field calculations. ... 

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