The annual four day intensive course on the Interpretation of Infrared Spectra will be held 8 - 11 November 1999. Participants will concentrate on practical interpretation of infrared spectra for the majority of the course, being guided though many examples of both typical and a-typical spectra. Building on a foundation of generating and using correlation tables on day one, the student will progress through a comprehensive set of fundamental group vibrations, and by the end of the course will have achieved a good working knowledge of spectral interpretation. This course also includes a brief resum of basic infrared theory and a presentation on
computer methods used in interpreting and matching infrared spectral data. Many
people have benefited from this course in recent years. For further details contact Monica Pope at Perkin-Elmer Ltd.
Courses can also be held at users sites.
The application of Raman spectroscopy in the analytical laboratory has now become a more common place event and with the introduction of new technologies such as CCD detection and holographic laser rejection filters the dispersive Raman microscope has become a truly bench-top tool. Introduction to Raman
Microscopy Instruments SA and its group divisions of Jobin Yvon, Dilor and SPEX developed the first commercial Raman microprobes in the early 1970's (1). Since then the technique has been refined and developed to provide an essential method for micro analysis (2). The Raman microprobe, based around the well characterised principles of the confocal pinhole and coupling optics (see Figure 1.) can provide the very highest spatial resolution - The latest systems can now reach close to the theoretical diffraction limit and typically analyse particles as small as one mm. When a motorised X,Y,Z stage is used, a full confocal Raman mapped image can be generated - invaluable to studies of dispersed particles and surface structure (see Figure 2.)
The LabRam Infinity It has long been the case that although the possible capabilities of the Raman microscope have proved attractive, Raman systems and in particular Raman microscopes have been often difficult in their operation and with only a fixed and inflexible configuration. As with all Raman instruments there are often many competing effects and processes that can have a great bearing on the quality of the data obtained. Fluorescence, sample heating, photo degradation, weak scattering efficiency can all produce adverse effects on the Raman spectrum. The limitations imposed by fixed configurations has led to the development of instruments which set out to solve these problems by offering flexible instrumentation where the laser source, laser power and resolution are easily adjusted to suit the varied samples found in the routine analytical and development laboratory. The LabRam Infinity Raman system (Figure 3.) has been specifically designed to give the analytical laboratory a lower cost yet high performance Raman microscope. One that also meets the flexibility and operational requirements demanded by the modern analytical laboratory. The aim being to provide the widest range of highly specific analysis of solid, liquid and solution samples that this technique can potentially offer to the analyst.
Flexibility is the
Key Within the unique optical design of the LabRam Infinity it is possible to incorporate features and facilities traditionally only found on larger high-end research instruments. The single chassis design also provides the ultimate in stability and so removes the need for any optical adjustment or alignment essential for a system that is to be used for fast routine analysis. The new Dual laser models offer two laser sources mounted internally. The advantage of having multiple laser sources and not just a single laser line is well known. For instance, with the 532nm/785nm dual option, high scattering efficiencies are provided by the green laser , whilst switching over to the NIR 785nm diode laser enables the user to often avoid fluorescence problems (Figures 4 and 5.). Other configurations, including HeNe and even UV laser sources can also be accommodated on such an instrument truly offering an unprecedented versatility.
To add further flexibility, the LabRam
infinity has dual gratings incorporated in the instrument. Again, a well established
advantage of the research grade instruments was to have the ability to change diffraction
gratings. Hence, this could enable the user to select different spectral resolutions. For
example, to offer Raman spectra with a high resolution grating and to offer a broader
fluorescence spectrum with a lower resolution grating. Moreover, if multiple lasers
sources were to be used the instrument could have gratings optimised for performance in
different regions, say 488nm and 785nm.
The Dual gratings used in the LabRam infinity now give this same versatility to the bench-top instrument. Automated Operation In addition to flexibility, a further prerequisite for the analytical instrument is to be able to operate the system with the minimum of effort and maximum of ease. The next generation of Raman microscopes such as, the LabRam Infinity now offer a very high level of automation. The Infinity is a truly unique 'turnkey' system where the selection of different lasers, spectral coverage and other facilities is all automated and requires no user intervention. To switch gratings or lasers is now trivial and accomplished in seconds by computer command. Laser (operator) Safety All this sophistication and flexibility is very fine but if the instrument is confined to a laser laboratory with restricted access, then its usefulness is greatly reduced. For this reason the LabRam Infinity was designed to meet class (I) laser safety protocols. The integral laser safety frame and tiered password protected software means that the inexperienced user is totally isolated from the laser sources. Of course, for the 'Raman traditionalist', or those users with large format cryostats the system can be operated with the frame open, provided they have the correct security password. In summary, the LabRam Infinity represents the next generation in analytical Raman microscopes. It offers the very highest level of performance and versatility, whilst its integrated and automated design means this system is regarded as almost a 'black box' instrument. References
For Further Information on the LabRam Infinity or any of the Raman instruments in the ISA range. Please contact
The (current) corporate sponsors for the meeting are
and
Technical Sponsors are:
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Introduction
to Infrared Spectroscopy
