Spectrometer static field

Static fields mass spectrometer. A mass spectrometer that can separate ion beams with fields that do not vary with time. These fields are generally electrostatic or magnetic. 

Static field spectrometer a spectrometer that separates the ion beams using fields that remain constant in time. 

As chemists performing spectroscopy, we are usually looking for the highest spectral resolution possible. Generally, one of the factors that limit the spectral resolution is the uniformity of B0 (the homogeneity of the static field) over the volume of the sample. If the field strength differs from point to point within the sample, there will be a similar point-to-point variation of Larmor frequency, and the width of the resonance line will reflect that distribution in frequency. The shim system (Section 3.2), which is used in a spectrometer to improve B0 homogeneity, consists of a set of electrical coils within the... 

Figure 3.45. The spectrometer lock system monitors the dispersion mode signal of the solvent deuterium resonance. A shift of the resonance frequency due to drift in the static field generates an error signal that indicates the magnitude and direction of the drift, enabling a feedback system to compensate this.

The significant improvements in sensitivity achieved during the last 5 years have been because of improved probe design and radiofrequency circuits. Since the probe needs to be located very close to the sample, it must be made of a material with a low magnetic susceptibility, for otherwise it would cause distortions of the static magnetic field thereby adversely affecting line shape and resolution. Much research has therefore been undertaken by NMR spectrometer manufacturers to develop materials that... 

---