Spectroscopic windows

In general, UXAS opens a new spectroscopic window for the direct ultrafast time-resolved observation of molecular motions during chemical reactions. (From Rose-Petruck, 2000)... 

Liquid range Spectroscopic windows Electrochemical windows ... 

A collection of UV/Vis, IR, as well as and NMR spectra of common organic solvents can be found in reference [147]. A comprehensive list with UV and IR spectroscopic windows of organic solvents is given in reference [8]. 

The ReactlR MP unit is designed from a safety and performance perspective for operations in manufacturing environments. One of the operational problems occasionally encountered with in-line spectroscopic techniques is fouling of optical components. To avoid fouling of the probe and to insure a clean spectroscopic window, the ReactlR MP is equipped with a 200-W ultrasonic... 

D-D stretching modes are often observed because of tbe clear spectroscopic window in rare-gas media (see Chapter 8). This is usually not a trivial measurement, however, as will be discussed later. 

Figure 1 Matrix apparatus as used in Nottingham (1) valve power supply, (2) helium pressure connections to compressor, (3) silicon diode and heater lead-through, (4) pump-out port, (5) gas inlet port, (6) cold station, (7) heater and thermocouple wires, (8) stainless steel tube, (9) silicon diode, (10) very cold station and heater sleeve, (11) cell, (12) photolysis and spectroscopic windows, for an experiment the cell is turned by 90° towards the windows, (13) vacuum shroud, (14) large half of cell, (15) small half of cell, (16) IR optical windows, (17) lead seal, (18) indium window seal, (19) circlip retainer groove, (20) bolt, (21) steel washer, (22) spring washer, (23) nut, (24) femal-femal union, (25) steel tubing, (26) to very cold station, (27) threaded copper stud, (28) threaded hole in large half of cell to receive stud, (29) indium joints, (30) circlip, which fits in groove and retains windows.

These halogenated solvents act as electron scavengers by dissociative electron attachment, leading to complexes between chloride ions and radicals that persist indefinitely in solids at low temperature. This leaves the holes to migrate through the solvent and attach to substrates that are easier to ionize than the solvent molecules, thus forming the targeted radical cation. The main limitation of the above methods is that the spectroscopic window for the observation of radical ions is usually limited to 300 -1400 nm (at the UV end by the electronic absorption of the neutral, in the NIR due to vibrational overtones of the solvent molecules). 

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