Basic Experimental Techniques

Though normal Raman spectroscopy is a very selective technique for chemical analysis, there are some serious experimental disadvantages related to the sensitivity, large fluorescence interference, and lack of time resolution of the technique. These weaknesses have been addressed in the creation of new Raman-based techniques. The weak Raman signals due to inherently small Raman scattering efficiencies has been addressed by resonance Raman, surface-enhanced Raman and SPP-Raman techniques. Fourier...

Daniel Frisbie

Optical Fiber Tip Microfabrication

Applications of Scanning Tunneling Microscopy (STM) III. Applications of Atomic Force Microscopy (AFM) IV. Other SPM Techniques and Applications Cantilever A projecting beam supported only at one end, the deflection of which is directly proportional to the force applied normal (perpendicular) to the beam axis. Constant-current feedback control Regulation of the piezoelectric scanner position based on the magnitude of the electron tunneling current in a scanning tunneling microscope....

Angle Resolved Photoelectron Spectra

A different situation occurs if a molecule is adsorbed at a surface and thereby fixed in space. For example, consider a rodlike molecule (e.g., CO) which, for a given final state M+, emits electrons preferentially in the direction of the molecular axis. In addition, assume that the emission probability is proportional to cos2 of the angle between molecular axis and electric vector E of the ionizing radiation. The system is fully described by three angles and the polarization of the radiation....

Magnetic Resonance As A Physical Phenomenon

Spin And Orbital Motion Electrons

Although the term nuclear magnetic resonance has been in use in the technical community since before World War II, some changes in terminology have accompanied the onset of the medical applications in the 1980s. Partly to avoid any fear on the part of patients that radioactive isotopes might be involved (they are not) and partly to forestall any confusion with the distinct discipline of nuclear medicine (which does utilize radioactive isotopes), the adjective nuclear is often dropped. The term...

Glossary

Nacl Bond Ftir Spectrum

Absorbance Vertical coordinate used for infrared spectra that is equal to the log of the reciprocal of the sample transmittance. Absorptivity Constant characterizing the capacity of a sample to absorb radiation of a specific wavelength, independent of sample thickness or concentration. Dipole moment Magnitude of the positive or negative charge constituting a dipole, multiplied by the spacing between the charges. Fermi resonance Quantum mechanical interaction between close-lying energy states of...

Info

And is usually abbreviated to the shorthand notation H4Y, with H representing the carboxylic hydrogen atoms. This reagent is extremely important because it forms simple 1 1 complexes with a metal ion, that is, one metal atom to one EDTA molecule of very high stability. Note that the latter is associated with the relatively large number (6) of points of attachment (4 x COO + 2 x N) of the ligand to the metal. In the now familiar pattern discussed above, the titration involves the buret addition...