A frequency-swept quadrupole mass filter

Marmet, P.; Proulx, Maryse

doi:10.1016/0020-7381(82)80047-8

Cited by 15 publications

(8 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Both quadrupoles, UQ (high-pressure, RF-only transfer quadrupole) and DQ (low-pressure, RF/DC-resolving quadrupole), are operated in the frequency mode, i.e. the frequency of the sinusoidal AC voltage is changed to select the desired m / z , while the amplitude of the DC component and that of the AC component remain constant. , Such a mode of operation allows us to cover a wide range of m / z , a beneficial feature if high m / z values are to be detected. For this purpose, dedicated power supplies, QSwide1 and QSwide2, were developed (JanasCard, Czech Republic).…”

Section: Experimental Sectionmentioning

confidence: 99%

Charged Ice Particle Beams with Selected Narrow Mass and Kinetic Energy Distributions

Spesyvyi

Žabka

Polášek

et al. 2023

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

Small ice particles play an important role in atmospheric and extraterrestrial chemistry. Circumplanetary ice particles that are encountered by space probes at hypervelocities play a critical role in the determination of surface and subsurface properties of their source bodies. Here we present an apparatus for the generation of low-intensity beams of single mass-selected charged ice particles under vacuum. They are produced via electrospray ionization of water at atmospheric pressure and undergo evaporative cooling when transferred to vacuum through an atmospheric vacuum interface. m/z selection is achieved through two subsequent quadrupole mass filters operated in the variable-frequency mode within a range of m/z values between 8 × 104 and 3 × 107. Velocity and charge of the selected particles are measured using a nondestructive single-pass image charge detector. From the known electrostatic acceleration potentials and settings of the quadrupoles the particle masses could be obtained and be accurately controlled. It has been shown that the droplets are frozen within the transit time of the apparatus such that ice particles are present after the quadrupole stages and finally detected. The demonstrated correspondence between particle mass and specific quadrupole potentials in this device allows preparation of beams of single particles with a repetition rate between 0.1 and 1 Hz with various diameter distributions from 50 to 1000 nm at 30–250 eV of kinetic energy per charge. This corresponds to velocities and particle masses quickly available between 600 m/s (80 nm) and 50 m/s (900 nm) and particle charge numbers (positive) between 103 and 104[e], depending upon size.

show abstract

Section: Experimental Sectionmentioning

confidence: 99%

Charged Ice Particle Beams with Selected Narrow Mass and Kinetic Energy Distributions

Spesyvyi

Žabka

Polášek

et al. 2023

J. Am. Soc. Mass Spectrom.

View full text Add to dashboard Cite

show abstract

“…A quadrupole power supply capable of frequency scans was described by Mellor (1971). Marmet and Proulx (1982) described a frequency swept quadrupole that was intended to give greater stability than a conventional quadrupole with the electronics available then. A frequency scan from 500 to 350 kHz was used to produce a spectrum from m/z ¼ 10 to 40 with better than unit resolution.…”

Section: Scanning With Frequency Sweepsmentioning

confidence: 99%

Linear quadrupoles in mass spectrometry

Douglas

2009

Mass Spectrometry Reviews

124

111

View full text Add to dashboard Cite

The use of linear quadrupoles in mass spectrometry as mass filters and ion guides is reviewed. Following a tutorial review of the principles of mass filter operation, methods of mass analysis are reviewed. Discussed are extensions of quadrupole mass filters to higher masses, scanning with frequency sweeps of the quadrupole waveform, operation in higher stability regions, and operation with rectangular or other periodic waveforms. Two relatively new methods of mass analysis the use of "islands of stability" and "mass selective axial ejection" are then reviewed. The optimal electrode geometry for a quadrupole mass filter constructed with round rods is discussed. The use of collisional cooling in quadrupole ion guides is discussed along with ion guides that have axial fields. Finally, mass analysis with quadrupoles that have large distortions to the geometry and fields is discussed. An Appendix gives a brief tutorial review of definitions of electrical potentials and fields, as well as the units used in this article.

show abstract

“…Previous researchers have used rf frequency modulation to select specific ions passing through a quadrupole mass filter. 21,22 Since the applied rf frequency appears in the denominator of the expression defining the stability parameter, q, for multipole ion guides, it follows that decreasing this frequency for any multipole increases the q value, thus increasing the low mass cutoff. In this way only high mass ions are allowed to pass through the octopole ion guide.…”

Section: Theorymentioning

confidence: 99%