Synthetic multilayers

Thallium hydrogen phosphate (TIAP) Synthetic Multilayers 100 5.75 0 (8)-Mg (12) Poisonous... 

The designations listed for these synthetic multilayers are commercial tradenames from different instrament manufacturers. A more generic approach is to classify them according to their d spacing. 

The analyzing crystal shown schematically in Fig. 8.14 has a flat surface. Flat crystals are used in scanning (sequential) spectrometers. Curved crystals, both natural and synthetic multilayers, are used in simultaneous spectrometers, electron microprobes, and for synchrotron X-ray spectrometry. The advantage to a curved crystal is that the X-rays are focused and the collimators replaced by slits, resulting in much higher intensities than with flat crystal geometry. This makes curved crystals excellent for analysis of very small samples. The use of a curved crystal and slits in a simultaneous spectrometer is illustrated schematically... 

Figure 8.17 (a) Schematic drawing of a TXRF system. From left to right is the X-ray source, the synthetic multilayer monochromator (Section 8.2.3.2), the thin sample on a support, the silicon drift detector (SDD) above the sample, and finally a beam stop, (b) A commercial TXRF spectrometer, the Bruker S2 PICOFOX with its laptop computer. The displayed spectrum shows the high S/N ratio. ( 2013 Bruker, Inc. www.bruker.com. Used with permission.)... 

A clever extension of the NIXSW method has been introduced by the Fadley group [83] synthetic multilayer films of typically 40 repeat units of [B4C/W] grown... 

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