Spectromicroscopy

Tonner B P, Dunham D, Droubay T, Kikuma J, Denlinger J, Rotenberg E and Warwick A 1995 The development of electron spectromicroscopy J. Eiectron Spectrosc. 75 309... 

B. Luerssen, S. Gunther, H. Marbach, M. Kiskinova, J. Janek, and R. Imbihl, Photoelectron spectromicroscopy of electrochemically induced oxygen spillover at the Pt/YSZ interface, Chem. Phys. Lett. 316, 331-335 (2000). 

The advantage of Raman spectromicroscopy is that very small specimens can be studied while still allowing the determination of the second and fourth moments of the ODF. However, the expressions for the Raman intensities are more complex since the optical effects induced by the microscope objective have to be considered. Although the corrections may be small, they are not necessarily negligible [59]. This problem was first treated by Turrell [59-61] and later by Sourisseau and coworkers [5]. Turrell has mathematically quantified the depolarization of the incident electric field in the focal plane of the objective and the collection efficiency of the scattered light by high numerical aperture objectives. For brevity, only the main results of the calculations will be presented. Readers interested in more details are referred to book chapters and reviews of Turrell or Sourisseau [5,59,61]. The intensity in Raman spectromicroscopy is given by [59-61]... 

Silk fibers, a basic system with a uniaxial symmetry, have also been investigated by Raman spectromicroscopy [63] that is one of the rare techniques capable of providing molecular data on such small (3-10 pm diameter) single filaments. The amide I band of the silk proteins has been particularly studied to determine the molecular orientation using the cylindrical Raman tensor approximation. In this work, it was assumed that Co Ci, C2 and the a parameter was determined from an isotropic sample using the following expression of the depolarization ratio... 

Figure 10 shows polarized spectra of two types of silks recorded by Raman spectromicroscopy the dragline silk (the lifeline) of the spider Nephila edulis and the cocoon silk of a wild silkworm Sarnia cynthia ricini. The position of the amide I band at 1,668-1,669 cm-1 for both threads is characteristic of the /i-sheet... 

The biaxial orientation in photoaddressable azobenzene films has been observed recently by polarized Raman spectromicroscopy [64]. Here, IR spectroscopy has been advantageously used as a complementary technique to measure the order... 

Finally, as in macro-Raman experiments, orientation-insensitive spectra can also be calculated for spectromicroscopy. A method has been developed recently for uniaxially oriented systems and successfully tested on high-density PE rods stretched to a draw ratio of 13 and on Bombyx mori cocoon silk fibers [65]. This method has been theoretically expanded to biaxial samples using the K2 Raman invariant and has proved to be useful to determine the molecular conformation in various polymer thin films [58]. 

D. Vobornik, PhD thesis Scanning near-field Infrared Microscopy and Spectromicroscopy Applied to Nano-systems and Cells. Lausanne, 2005. 

Prietzel J,Thieme J, Neuhausler U, Susini J, Kogel-Knabner I. Speciation of sulphur in soils and soil particles by X-ray spectromicroscopy. Eur. J. Soil Sci. 2003 54 423-433. 

When this was first realized, we decided to demonstrate the photoelectron version of resonance MPI spectromicroscopy, for in that case the problem of the reproducibility of the results is simplified because there is no thermal desorption of the molecules and their photofragmentation is absent. 

In conclusion I would like to emphasize that the suggested approach (femtosecond laser spectromicroscopy) is not a simple modification of the Muller microscope [6], for the electric field here is not the decisive factor but serves solely to form the image. Table I lists the comparative characteristics of the Muller projection field-ion microscope (FIM) and proposed laser resonance photoelectron (photoion) spectromicroscope (LRFSM). 

Comparison of Characteristics of Field-Ion Microscopy (FIM) and Laser Resonance Photoion (Electron) Spectromicroscopy (LRFSM)... 

No analytical method is perfect. Spectral interpretation is still difficult, and standard spectra databases are scarce. The issues of quantification, comparison with data collected by other methods, and scale up are important, especially in spectromi-croscopy studies. Radiation damage and sectioning artifacts can make analysis of susceptible samples difficult. The biggest obstacle to widespread use of NEXAFS spectroscopy, microscopy, and spectromicroscopy in environmental studies remains the extremely limited number of such instruments. Typically, each beamline allocation committee receives 2 or 3 times as many requests for time as is available. Studies, when granted, are usually for 2-5 days every 4-6 months. Thus, scientists have to be very selective about the types of questions and samples that they choose to examine using these techniques. Continued pressure and education from the scientific community will be needed to increase the number of beamlines suitable for NOM studies in the future, even as new synchrotron facilities are planned or built. 

Brandes, J. A., Ingall, E., and Paterson, D. (2007). Characterization of minerals and organic phosphorus species in marine sediments using soft X-ray fluorescence spectromicroscopy. Marine Chem. 103, 250-265. 

Haberstroh, P. R., Brandes, J. A., Gelinas, Y., Dickens, A. F., Wirick, S., and Cody, G. (2006). Chemical composition of the graphitic black carbon fraction in riverine and marine sediments at submicron scales using carbon X-ray spectromicroscopy. Geochim. Cosmochim. Acta 70,1483-1494. 

Hitchcock, A. P., Stover, H. D., Croll, L. M., and Childs, R. F. (2005b). Chemical mapping of polymer microstructure using soft X-ray spectromicroscopy. Austr. J. Chem. 58,423 432. 

Myneni, S. C. B. (2002). Soft X-ray spectroscopy and spectromicroscopy studies of organic molecules in the environment. In Applications of Synchrotron Radiation in Low-Temperature Geochemistry and Environmental Sciences, Fenter, R, Rivers, M., Sturchio, N, and Sutton, S., eds., Rev. Mineralogy Geochem. 49,485-579. 

Neuhausler, U. (1999). Soft x-ray spectromicroscopy on hydrated colloidal and environmental samples. Ph.D. thesis, University of Gottingen. 

Osanna, A., and Jacobsen, C. (2000). Principle component analysis for soft X-ray spectromicroscopy. In X-Ray Microscopy Proceedings of the Sixth International Conference, Meyer-Ilse, W., Warwick, T., and Attwood, D., eds., American Institute of Physics, Melville, New York, pp. 350-357. 

Plaschke, M., Rothe, J., Denecke, M. A., and Fanghanel, T. (2004). Soft X-ray spectromicroscopy of humic acid europium(III) complexation by comparison to model substances. 

Thieme, J., Prietzel, J., Tyufekchieva, N., Paterson, D., and McNulty, I. (2006). Speciation of sulfur in oxic and anoxic soils using X-ray spectromicroscopy. In Proceedings of the 8th International Conference on X-Ray Microscopy, IPAP Conference Series 7, pp. 318-320. 

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