Static-field mass analyzers

If one wishes to carry ont gas-phase experiments, that is, to manipulate mass-selected ions inside the mass spectrometer, ion-trap analyzers offer the broadest arsenal of experiments including unimolecular fragmentations as well as bimolecular reactions with sufficiently volatile neutral reagents. Consequently, the choice of analyzer is also an important point. Mass analyzers use static or dynamic electric or magnetic fields to separate the ions either in time or in space. Sector-field mass analyzers use magnetic (B) and electrostatic (E) sectors to separate the ions... 

Much of the work in the early development of the preceding techniques incorporated pulsed electron-impact ionization sources or any of several types of laser ionization techniques. In almost all of these cases the ions were created in a pulsed fashion in vacuum and formed in or sent into the acceleration region of the mass spectrometer, where a static acceleration field present there injected them into the mass spectrometer. Such ion sources use the TOF-MS very efficiently because the repetition rate of the spectrometer is limited by the frequency of the ionization event itself. This arrangement allows the TOF-MS to mass analyze of all of the ions formed completely. However, many of the most popular ionization techniques being used in inorganic analysis today are continuous in nature. 

Quadrapole mass analyzers are by far the most common type of mass spectrometer in use today and the literature on these type of analyzers is extensive. Quadrapole mass analyzers are often thought of as mass filters because they can be tuned to transmit ions of a narrow range of mass/charge (w/z) ratios. Fig. 6 shows a generalized block schematic of a quadrapole mass spectrometer. A typical quadrapole instrument separates ions with different masses by application of a combination of static and radio frequency electric fields to four cylindrical rods. A headspace gas sample is introduced at an inlet and fed into an ion source where electrons are emitted from a filament and ionize the sample gas. The sample ions are then accelerated in an electrical field and are injected into the opening at the center of the rods. In the simplest systems, one pair of rods is connected and attached to the positive... 

In its most fundamental form, ion implantation is a process by which energetic, charged-particles or impurity atoms can be introduced into a target or substrate material. Often, these particles which are to be implanted are positive ions (singly or multiply ionized) which come from a suitable source. After the formation of the positive ions, they are accelerated by static electric fields, are focused or formed into a beam, and are passed through a mass analyzer. The mass analyzer is used to ensure that the beam is pure. 

Sector field analyzers are magnetic or electric sector fields or a combination of the two with ion focusing and separation properties used in static mass spectrometers. 

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