scholarly journals Preparation and Study of Single Sized Cluster Ions in a Supersonic Jet

1991 ◽  
Vol 11 (3-4) ◽  
pp. 225-230 ◽  
Author(s):  
E. W. Schlag ◽  
H. L. Selzle
Keyword(s):  
Mass Spectrometer ◽  
Time Scale ◽  
Supersonic Jet ◽  
Excess Energy ◽  
Cluster Ions ◽  
Mass Analysis ◽  
Two Photon ◽  
Supersonic Jet Expansion ◽  
Photon Ionization ◽  
Single Size

Experiments with supersonic jet expansion have been performed to prepare clusters of benzene molecules. The clusters produced in the jet are ionized by two-photon ionization and mass analysis is achieved in a reflectron time of flight mass spectrometer. Due to an excess energy up to several hundred me V unimolecular decay occurs on a time-scale from nanoseconds up to microseconds and even longer. To discriminate against interferences from fragmentation of higher mass clusters in the observed spectra different experiments have been performed which include a new method by which single size cluster ions are stopped in the supersonic jet. These ions then stay isolated in space and the metastable decay of these complexes can be analyzed without further perturbation from fragmentation of higher clusters.

Analytical Jet Spectroscopy of Tyrosine and its Analogs Using a Pulsed Laser Desorption Volatilization Method

1988 ◽  
Vol 42 (3) ◽  
pp. 418-424 ◽  
Author(s):  
Liang Li ◽  
David M. Lubman
Keyword(s):  
Structural Changes ◽  
Electronic Spectroscopy ◽  
Supersonic Jet ◽  
Pulsed Laser ◽  
Laser Desorption ◽  
Ultracold Molecules ◽  
Two Photon ◽  
Biological Compounds ◽  
Supersonic Jet Expansion ◽  
Photon Ionization

Pulsed laser desorption is used as a means of volatilizing nonvolatile and thermally labile molecules for entrainment into a supersonic jet expansion. The jet expansion provides ultracold molecules whose sharp spectral features are probed by resonant two-photon ionization spectroscopy in a time-of-flight mass spectrometer. Such jet-cooled spectra are demonstrated for tyrosine and related structural analogs. Despite the similarity between these tyrosine-based compounds, electronic spectroscopy is shown to be a sensitive probe of small structural changes in these related biological compounds.

A New Liquid Droplet Laser Desorption Source Combined with Supersonic Jet Expansion: Application to Phenol and its Water Clusters

2014 ◽  
Vol 228 (4-5) ◽  
Author(s):  
Chayan Kanti Nandi ◽  
Hans-Dieter Barth ◽  
Bernhard Brutschy
Keyword(s):  
Gas Phase ◽  
Water Clusters ◽  
Liquid Droplet ◽  
Supersonic Jet ◽  
Laser Desorption ◽  
Laser Source ◽  
Published Data ◽  
Two Photon ◽  
Supersonic Jet Expansion ◽  
Phase Out

AbstractWe have developed a new laser source, for the spectroscopy of nonvolatile molecules in gas phase. It is based on a laser induced liquid bead ion desorption source (LILBID) combined with a supersonic beam. The cold molecules produced with this technique are sampled with Resonant Two Photon Ionization spectroscopy (R2PI) to measurement of the gas phase optical spectra. LILBID allows to bring nonvolatile molecule from liquid phase (out of a droplet) into gas phase, by means of multi photon ablation with IR photons exciting the vibrations of the solvent. Phenol and its different water clusters have been used as an example to demonstrate the method and to standardise the new experimental setup. The recorded R2PI spectral data of phenol monomer and its different water clusters obtained from this laser desorption technique are in very good agreement with the previously published data. This technique opens a new door for the measurement of molecules under microsolvation and potentially for

Two-Photon Ionization of Polyatomic Molecules in a Mass Spectrometer

1978 ◽  
Vol 33 (12) ◽  
pp. 1546-1548 ◽  
Author(s):  
U. Boesl ◽  
H. J. Neusser ◽  
E. W. Schlag
Keyword(s):  
Mass Spectrometer ◽  
Polyatomic Molecules ◽  
Dye Laser ◽  
Ionization Source ◽  
Two Photon ◽  
Photon Ionization ◽  
Tunable Frequency

Abstract Two-photon ionization of benzene molecules in a mass spectrometer is performed with a tunable frequency-doubled dye laser. The nonlinear ionization is resonantly enhanced by real intermediate rovibronic levels in the S1 state of the molecule. Our results show that stepwise multi-photon ionization is a very selective and versatile ionization source for a mass spectrometer.

Dependence of the laser two-photon ionization signal of anthracene on the electron mobility and the excess energy in non-polar solvents

1995 ◽  
Vol 299 (3) ◽  
pp. 355-360 ◽  
Author(s):  
Teiichiro Ogawa ◽  
Miki Sato ◽  
Makoto Tachibana ◽  
Kazuhiko Ideta ◽  
Takanori Inoue ◽  
...  
Keyword(s):  
Electron Mobility ◽  
Excess Energy ◽  
Polar Solvents ◽  
Two Photon ◽  
Ionization Signal ◽  
Photon Ionization

Formation of protonated ammonia cluster ions: Two‐color two‐photon ionization study

1993 ◽  
Vol 98 (1) ◽  
pp. 336-341 ◽  
Author(s):  
Fuminori Misaizu ◽  
Paul L. Houston ◽  
Nobuyuki Nishi ◽  
Hisanori Shinohara ◽  
Tamotsu Kondow ◽  
...  
Keyword(s):  
Cluster Ions ◽  
Two Photon ◽  
Photon Ionization ◽  
Ammonia Cluster Ions

Kinetic energy of fragment ions in a radiofrequency mass spectrometer

1965 ◽  
Vol 286 (1405) ◽  
pp. 178-190 ◽  
Keyword(s):  
Kinetic Energy ◽  
Mass Spectrometer ◽  
Mass Spectra ◽  
Electronic States ◽  
Slight Modification ◽  
Polyatomic Molecules ◽  
Excess Energy ◽  
Mass Analysis ◽  
Effective Competition ◽  
Fragment Ions

A radiofrequency mass spectrometer has been used, with slight modification, to measure the kinetic energy of fragment ions from polyatomic molecules. Selected ions from CO 2 , CH 3 OH, C 2 H 5 OH, C 3 H 7 OH, i-C 3 H 7 OH, CH 3 I and C 2 H 5 I were examined for excess kinetic energy by means of retarding potential analysis before mass analysis. The excess kinetic energy for any given ion was always greater for 70 V electron impacts than for 50 V. Such ions as m/g 31 and 29 from ethanol have an excess of about 0·45 V kinetic energy for 50 and 70 V electrons; m/q 29 and 27 from isopropanol also have about 0·45 excess energy for 70 V electrons; CH + 3 ions from the alcohols and from the iodides showed excess kinetic energy while m/q 27 from ethyl iodide had 0·9 V excess energy for 70 V electrons. The results are interpreted as evidence of a significant num ber of dissociations from electronic states which are not in effective competition with one another. The existence of non ­ competing dissociation paths for a given molecular ion complex would preclude the application of the statistical theory of mass spectra to predict the breakdown scheme of that complex.

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