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Fragmentation is a type of chemical dissociation, in which the removal of the electron from the molecule results in ionization. Removal of electrons from either sigma bond, pi bond or nonbonding orbitals causes the ionization. [2] This can take place by a process of homolytic cleavage or homolysis or heterolytic cleavage or heterolysis of the ...
Mass spectral interpretation is the method employed to identify the chemical formula, characteristic fragment patterns and possible fragment ions from the mass spectra. [1] [2] Mass spectra is a plot of relative abundance against mass-to-charge ratio. It is commonly used for the identification of organic compounds from electron ionization mass ...
A mass spectrum is a histogram plot of intensity vs. mass-to-charge ratio (m/z) in a chemical sample, [1] usually acquired using an instrument called a mass spectrometer. Not all mass spectra of a given substance are the same; for example, some mass spectrometers break the analyte molecules into fragments ; others observe the intact molecular ...
The results are presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures. A mass spectrum is a type of plot of the ion signal as a function of the mass-to-charge ratio.
A schematic diagram of chemical ionization source. Chemical ionization (CI) is a soft ionization technique used in mass spectrometry. [1] [2] This was first introduced by Burnaby Munson and Frank H. Field in 1966. [3] This technique is a branch of gaseous ion-molecule chemistry. [2]
In the selected ion flow tube mass spectrometer, SIFT-MS, ions are generated in a microwave plasma ion source, usually from a mixture of laboratory air and water vapor. . From the formed plasma, a single ionic species is selected using a quadrupole mass filter to act as "precursor ions" (also frequently referred to as primary or reagent ions in SIFT-MS and other processes involving chemical ...
The mass spectrum can be used to determine the mass of the analytes, their elemental and isotopic composition, or to elucidate the chemical structure of the sample. [5] MS is an experiment that must take place in gas phase and under vacuum (1.33 * 10 −2 to 1.33 * 10 −6 pascal).
Schematic of field desorption ionization with emitter at left and mass spectrometer at right. Field desorption (FD) is a method of ion formation used in mass spectrometry (MS) in which a high-potential electric field is applied to an emitter with a sharp surface, such as a razor blade, or more commonly, a filament from which tiny "whiskers" have formed.