Magnetic/electrostatic analyzer

Magnetic/electrostatic analyzer-collision cell-quadmpole... 

Figure 2.1 Mass spectrometric approach. Dl, direct inlet GC, gas chromatography HPLC, high performance liquid chromatography CZE, capillary zone electrophoresis El, electron ionization Cl, chemical ionization ESI, electrospray ionization DESI, desorption electrospray ionization APCI, atmospheric pressure chemical ionization MALDI, matrix assisted laser desorption ionization B, magnetic analyzer E, electrostatic analyzer...

No one single mass analyzer is suitable for all applications and the choice of instrument is determined by the type of problem under investigation [68]. Double focusing magnetic/electrostatic sectorfield-, quadrupole-, quadrupole ion trap-, time-... 

Time of flight is surely the simplest mass analyzer (Wollnik, 1993). In its basic form, it consists of an ion accelerator and a flight tube under vacuum. Magnetic, electrostatic, and electrodynamic fields are no... 

Fig. 15.3. Medium current beamline showing an electric scanner and electrostatic parallelizing lens. The ion source, analyzer magnet, and resolving aperture serve to inject the unscanned beam from the left. The parallel scanned beam on the right is passed through a postacceleration column and an electrostatic deflector before reaching the wafer...

Fig. 8.2. Schematic of AMS set-up. Various parts like negative ion source, analyzing magnet, accelerating tube, carbon stripping foil, detector, and electrostatic analyzer are shown...

A time-of-flight mass analyzer (TOF-MS) does not depend on a magnetic, electrostatic, or RF field to disperse or filter ions for individual m/z ion detection. A pulsed polyatomic ion beam is accelerated to a constant kinet-... 

There are many types of high resolution analyzers with electrostatic and magnetic sectors. It is impossible to cover them all in this chapter because their characteristics vary significantly from model to model and high resolution systems are less standardized than quadrupolar devices. 

The double-focusing combination of electrostatic- and magnetic-sector analyzers allows the inherent energy spread of the beam to be compensated for by design and ensures that there is no spread in the beam at the collector. 

Double-focusing analyzer. A magnetic analyzer and an electrostatic analyzer combined in either sequence to effect direction and velocity focusing. 

Electrostatic analyzer. A velocity-focusing device for producing an electrostatic field perpendicular to the direction of ion travel (usually used in combination with a magnetic analyzer for mass analysis). The effect is to bring to a common focus all ions of a given kinetic energy. 

Mass spectrometer configuration. Multianalyzer instruments should be named for the analyzers in the sequence in which they are traversed by the ion beam, where B is a magnetic analyzer, E is an electrostatic analyzer, Q is a quadrupole analyzer, TOP is a time-of-flight analyzer, and ICR is an ion cyclotron resonance analyzer. For example BE mass spectrometer (reversed-geometry double-focusing instrument), BQ mass spectrometer (hybrid sector and quadrupole instrument), EBQ (double-focusing instrument followed by a quadrupole). 

Neir-Johnson geometry. An arrangement for a double-focusing mass spectrometer in which a deflection of nil radians in a radial electrostatic-field analyzer is followed by a magnetic deflection of 7t/3 radians. The electrostatic analyzer uses a symmetrical object-image arrangement, while the magnetic analyzer is used asymmetrically. 

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