Molecular ion images

D. Touboul, F. Halgand, A. Brunelle, R. Kersting, E. Tallarek, B. Hagenhooo and O. Laprevote, Tissue molecular ion imaging by gold cluster ion bombardment, Analytical Chemistry, 76, 1550 1559(2004). 

Touboul D, Halgand F, Brunelle A, Kersting R, Tallarek E, Hagenhoff B, Laprevote O (2004) Tissue molecular ion imaging by gold cluster ion bombardment. Anal Chem 76 1550-1559. doi 10.1021/ac... 

Creating Molecular Ion Images of DIstrlbuVons of NeuropepVdes with Similar Molecular Masses... 

Fig. 1. Schematic diagram of the multimass ion imaging detection system. (1) Pulsed nozzle (2) skimmers (3) molecular beam (4) photolysis laser beam (5) VUV laser beam, which is perpendicular to the plane of this figure (6) ion extraction plate floated on V0 with pulsed voltage variable from 3000 to 4600 V (7) ion extraction plate with voltage Va (8) outer concentric cylindrical electrode (9) inner concentric cylindrical electrode (10) simulation ion trajectory of m/e = 16 (11) simulation ion trajectory of rri/e = 14 (12) simulation ion trajectory of m/e = 12 (13) 30 (im diameter tungsten wire (14) 8 x 10cm metal mesh with voltage V0] (15) sstack multichannel plates and phosphor screen. In the two-dimensional detector, the V-axis is the mass axis, and V-axis (perpendicular to the plane of this figure) is the velocity axis (16) CCD camera.

Secondary ion (mass spectrometry) SIMS Particle induced desorption/ ionization Nonvolatile molecular ions Semiconductors Surface analysis Imaging... 

TOF-SIMS has been employed for the characterization of a wide range of materials, including metallic, salt, organometallic, organic, and polymeric substances, as well as for electronics, catalysts, and forensic samples. The ability to image molecular ions with submicrometer spatial resolution makes TOF-SIMS well suited to analysis of pharmaceuticals and biological cells, as well as for use in biotechnology and molecular electronics. 

Spectroscopy produces spectra which arise as a result of interaction of electromagnetic radiation with matter. The type of interaction (electronic or nuclear transition, molecular vibration or electron loss) depends upon the wavelength of the radiation (Tab. 7.1). The most widely applied techniques are infrared (IR), Mossbauer, ultraviolet-visible (UV-Vis), and in recent years, various forms ofX-ray absorption fine structure (XAFS) spectroscopy which probe the local structure of the elements. Less widely used techniques are Raman spectroscopy. X-ray photoelectron spectroscopy (XPS), secondary ion imaging mass spectroscopy (SIMS), Auger electron spectroscopy (AES), electron spin resonance (ESR) and nuclear magnetic resonance (NMR) spectroscopy. 

See Contact stress Hexagonal symmetry 132 Hohenberg-Kohn theorem 113 Hydrogen molecular ion 173 history 173 repulsive force 185 resonance interaction 177 van der Waals force 175 Hydrogen on silicon 336 Image force 56—59, 72, 93 concept 56 effect on tunneling 74 field emission, in 56 jellium model, in 93 observability by STM 72... 

Figure 6.1. The Jovian moon lo deep ultraviolet (UV) photolysis of its methane atmosphere proceeds with electron ejection, generating the molecular ion of methane (see color insert). NASA JPL Galileo program image from Voyager 1, http //www.jpl.nasa.gov/galileo/io/...

SIMS ions ions ZZ sputtered ions > 1 nm 50 nm + + + > ngg 1 high depth resolution good imaging huge variation of RSCs, intense molecular ions... 

Computer-generated structure of two of the four subunits of phosphofructokinase from Bacillus stearothermophilus. The enzyme, shown as yellow and light blue tubes, was crystallized in the R conformation in the presence of the substrate fructose-6-phosphate (dark blue) and the allosteric activator ADP (pink). The magnesium ions (white/silver spheres), Mg2+, bound to the ADP molecules are also shown. (Copyright 1994 by the Scripps Research Institute/Molecular Graphics Images by Michael Pique using software by Yng Chen, Michael Connolly, Michael Carson, Alex Shah, and AVS, Inc. Visualization advice by Holly Miller, Wake Forest University Medical Center.)... 

Ultrafast molecular elimination of iodine from IF2C-CF2I has been studied using the velocity map ion imaging technique in combination with femtosecond pump-probe laser excitation.51 By varying the femtosecond delay between pump and probe pulse, it has been found that elimination of molecular iodine is a concerted process, although the two carbon-iodine bonds are not broken synchronously. 

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