Spectrometer theoretical resolving power

Eqs. 3.1-19 and 3.1-25, which describe the relation between the characteristics of gratings and prisms and the theoretical resolving power Ro, give the optical conductance of grating and prism spectrometers. We may write... 

While the diffusion-limited resolving power estimates the possible separation power of an ion mobility spectrometer, the theoretical resolving power determines its separation power by taking the additional consideration of the actual operation parameters, such as the ion shutter pulse width and pressure as... 

The efficiency of an ion mobility spectrometer can be computed by expressing the experimental resolving power as a percentage of the theoretical resolving power as... 

Ro theoretical resolving power of optical spectrometer RSF relative sensitivity factor in elemental mass spectrometry... 

Probably the simplest mass spectrometer is the time-of-fiight (TOP) instrument [36]. Aside from magnetic deflection instruments, these were among the first mass spectrometers developed. The mass range is theoretically infinite, though in practice there are upper limits that are governed by electronics and ion source considerations. In chemical physics and physical chemistry, TOP instniments often are operated at lower resolving power than analytical instniments. Because of their simplicity, they have been used in many spectroscopic apparatus as detectors for electrons and ions. Many of these teclmiques are included as chapters unto themselves in this book, and they will only be briefly described here. 

The resolving power of a spectrometer is its ability to separate adjacent spectral lines. This theoretical concept is given by the dimensionless parameter R such that ... 

Shoosmith, 1956) shows two main feamres at 215.7nm and 216.3 nm but does not show any significant rotational structure as a result of the rapid dissociation of the CH3 excited electronic level. Childs et al. (1992) were able to resolve the two features in the CH3 absorption spectrum with a spectral resolution of 0.12nm, which was about 3 times the theoretical resolution limit of 0.04 nm for their instrument. For most measurements, however, Childs et al. (1992) used the spectrometer at a lower spectral resolving power with the input slits opened up and with the averaging of neighboring pixels, since the width of the CH3 absorption feature at 216.3 nm is 1.2nm. Although the two features of the CH3... 

Several expressions are used to describe the separation efficiency of ion mobility spectrometry. These include the peak width at half height, wi/2, the resolving power, Rp, and the number of theoretical plates, N. These terms can be expressed in theory and from experimental data. The peak width at half height is the width of a mobility peak at 50% of its height, and it has units of milliseconds. The experimental resolving power of an ion mobility spectrometer is determined by measuring the drift time (fu) and peak... 

According to the Rayleigh criterion, the theoretical resolution AAtheor. which could be produced by a spectrometer, is given by the theoretical diffraction-limited resolving power i theor ... 

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