Search results for "Fourier transform ion cyclotron resonance"
showing 10 items of 70 documents
Precision Determination of Cyclotron Frequencies of Free Electrons and Ions
1982
Within the last two decades the electrodynamical storage of electrons and ions developed into an experimental method of great versatility. That this method is now being used in so many different fields of physics and chemistry results primarily from the long storage times which nowadays can be achieved. Under ultrahigh vacuum conditions and in sufficiently strong electromagnetic fields the particles can easily be trapped for hours or even days. This really long storage time offers the possibility of studying reactions of very slow rate to the chemist and of precision measurement of photon-ion interactions to the physicist. The accuracy of photon-ion interaction measurement is finally limite…
The influence of the trapping potential on the attachment of a second electron to stored metal cluster and fullerene anions
2002
Abstract Singly charged anionic clusters are exposed to a bath of simultaneously stored electrons in ion cyclotron resonance (Penning) traps and thus, dianions are produced. The dianion yield is found to be a function of the potential well depth. As an example, the attachment of electrons to size-selected gold cluster anions Au 25 1− from a laser vaporization source has been studied in detail by time-of-flight mass analysis after ejection of all ions from the trap. Furthermore, the investigation is extended to fullerene anions C 70 1− that are produced by laser desorption from a fullerene target in the external source of a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer…
Recent gold cluster studies in a Penning trap
2002
Abstract A progress report is given on the investigation of metal clusters with an ion cyclotron resonance (Penning) trap. The examples are taken from the recent studies on gold clusters. In particular, the monomer and dimer evaporation is monitored as a function of cluster size. For the particular case of Au 7 + this study is expanded to include the energy dependence of the branching ratio. In connection with the sequential decay of Au 8 + the information can be used for a model-free determination of the dissociation energy of Au 8 + . A second line of studies concerns the production, properties and storage behavior of polyanionic gold clusters. Such species have recently been produced by …
ESI-FTICR investigation of triethylammonium ion-driven resorcin[4]arene dimer formation and structure
2002
In the course of mass spectrometric measurements a self-assembled hydrogen bonded resorcinarene dimer was observed, the formation of which was driven by the binding of triethylammonium ion as a guest and as an ionic label.
Mass Spectrometric Investigation of Noncovalent Complexation between a Tetratosylated Resorcarene and Alkyl Ammonium Ions
2004
Noncovalent complexation between tetratosylated tetraethyl resorcarene (1) and primary, secondary, and tertiary alkyl ammonium ions (mMe, dMe, tMe, mEt, dEt, tEt, dBu, and dHex) was studied by electrospray ionization Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry. Interactions of the noncovalent complexes were investigated by means of competition experiments, collision-induced dissociation (CID) experiments, ion-molecule reactions with tripropylamine and gas phase H/D-exchange reactions with deuteroammonia. Gas phase ion-molecule reactions gave especially valuable information about the structure and properties of the complexes. Resorcarene 1 formed relatively stable…
Foodomics assessed by Fourier transform mass spectrometry
2019
Abstract With its ultrahigh resolution power and excellent mass accuracy, Fourier transform ion cyclotron resonance mass spectrometry is the perfct tool to analyze the “foodome” as the set of all polar small molecular compounds present in an investigated food sample. We present here selected applications of this technique in unraveling the metabolome in complex foods (thermally affected, fermentation products, distillates) such exemplified with Maillard reaction products or with wines and spirits. Technical considerations for high resolution mass analyzers are provided from a practical point of view. Moreover, aspects of food safety and nutritional quality are covered by presenting applicat…
Quantitative Spatial Analysis of the Mouse Brain Lipidome by Pressurized Liquid Extraction Surface Analysis
2014
Here we describe a novel surface sampling technique termed pressurized liquid extraction surface analysis (PLESA), which in combination with a dedicated high-resolution shotgun lipidomics routine enables both quantification and in-depth structural characterization of molecular lipid species extracted directly from tissue sections. PLESA uses a sealed and pressurized sampling probe that enables the use of chloroform-containing extraction solvents for efficient in situ lipid microextraction with a spatial resolution of 400 μm. Quantification of lipid species is achieved by the inclusion of internal lipid standards in the extraction solvent. The analysis of lipid microextracts by nanoelectrosp…
Alkali metal mediated resorcarene capsules: An ESI-FTICRMS study on gas-phase structure and cation binding of tetraethyl resorcarene and its per-meth…
2002
AbstractElectrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICRMS) with additional ab initio calculations were used to examine the alkali metal cation binding selectivity (i.e., molecular recognition) and host properties of tetraethyl resorcarene (1) and its per-methylated derivative (2). The significance of intramolecular hydrogen bonding for the crown conformation was demonstrated. The presence of intramolecular flip-flop hydrogen bonding in 1 was confirmed both with calculations and in ND3-exchange experiments. All the alkali metal cations formed host–guest complexes by docking inside the cavity of the host. Complexation with the larger cations, esp…
Mass spectrometric studies on small open-chain piperazine-containing ligands and their transition metal complexes
2001
Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry was used to characterize the complexes formed between open-chain piperazine-containing ligands and transition metal salts (Cobalt, Copper, Zinc, and Cadmium as chlorides, nitrates, and acetates). Only single-charged complexes were observed, formed of one ligand (L) and mainly one metal ion (M). Since the net charge of the complexes was one, a counterion (X) was attached to some of the complexes, with formation of [L + M + X]+ complexes, and a proton was lost from others, as in [L − H + M]+ complexes. In most cases the composition of the complexes was more dependent on the ligand than the metal salt. Collisio…
Effect of the gas mixing technique on the production efficiency of ion beams extracted from an electron cyclotron resonance ion source
2004
In this work the effect of gas mixing on the production efficiency of ion beams extracted from an ECR ion source has been studied with the JYFL 6.4 GHz electron cyclotron resonance ion source (ECRIS). It was found that the gas mixing affects strongly the confinement of ions in the plasma of the ECRIS. The information obtained can be used to minimize the consumption of expensive materials or isotopes and to reduce contamination of the plasma chamber. It was observed that the carbon contamination, which is built up when the MIVOC method is used could be decreased with the aid of the gas mixing technique. The best mixing gas for this purpose was found to be oxygen.