This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Objectives ?The objectives stated in the recent renewal proposal are these: we will improve our current single crystal UV/Vis microspectrophotometry facility to provide optical spectra from single crystals in an essentially seamless and routine fashion at the X-ray beamline, and develop both single crystal fluorescence spectroscopy and single crystal Raman spectroscopy. Results ?Our current configuration at beamline X26-C consists of a Crystal Logic diffractometer with an ADSC Q210 area detector (on loan from the NSLS), a 4DX-ray Systems AB optical system, a Newport 75W Xe research arc lamp, a Newport 200W Hg (Xe) research arc lamp, an Ocean Optics USB 4000 CCD-based spectrophotometer running through the beamline controls on a LINUX operating systems, and an Horiba Jobin-Yvon Inc. Raman system consisting of two diode lasers (532 and 785 nm), a Raman probe head specific for each laser, an IHR 550 spectrometer and Synapse CCD detector. We have ordered a 473 nm diode laser and associated Raman probe head for Horiba Jobin-Yvon and are awaiting delivery and installation. X-ray diffraction and optical absorption data collection are fully integrated and controlled by the beamline-control software. Additional capabilities have been added to the beamline software, including the ability to track in real-time absorption changes at specific wavelengths and to convert frame number to radiation dose using the RADDOSE program. The results are linked directly to our database tracking system, the PXdb. The Raman system is fully operational with vibrational spectra routinely collected before and after x-ray exposure. Currently, the Raman system is controlled by the Windows-based LabSpec software provided by Horiba-JY. The optical absorption spectra collection utilizes UV/vis light (300 - 850 nm) from either a Xe or a Hg (Xe) arc lamp source. The light is brought to the sample and the transmitted light brought to the spectrophotometer via through quartz optical fibers. The 15x microscope objectives are based upon the Schwarzschild parabolic mirror design, which uses an all-reflecting principle and are, therefore, free from chromatic aberration. The light is focused to a spot size that depends upon objective and the diameter of the optical fiber to which it is connected. For example, the incident photons are focused to 25 ?m diameter spot through a 50 ?m optical fiber, whereas photons are collected through a 75 ?m diameter region focused by a 400 ?m optical fiber. This arrangement yields full range electronic absorption spectra typically in less than one second. Find a full description in the Progress Report entry. Plans ?Absorption spectroscopy ?We have expanded our capabilities into the UV region of the spectrum through the purchase of an Oriel Hg (Xe) arc lamp source. The arc lamp housing used for both lamps will been fitted with a 280 nm cut-up filter and filter holder in order to extend the lifetime of the fiber optic cables. To allow for remote control over the collection of absorption spectra, several modifications are underway. A purchased motorized shutter will control the output at the arc lamp source. Additional shutters are being designed for both the focusing and collection objectives. The control software will be amended such that remote operations becomes a reality. Diffractometer - The Q210 area detector will be returned to the NSLS in the near future. The Q315r detector, previously used at X25, will be installed at X26C. Non-resonance and Resonance Raman Spectroscopy - We have ordered a 473 nm laser and probe head. This will expand our resonance Raman capabilities. In the coming year, control of Raman data collection will be incorporated into the CBASS software and the operations will be automated. Tools will be developed to allow for the remote, computerized operation of the objective shutters, laser shutters, illumination lamps, room lights, etc. Off-line single-crystal spectroscopy ?An enclosure for off-line spectroscopy was constructed adjacent to the X26-C hutch in early 2010 and outfitted with an optical table, diffractometer/goniometer and cryostream. We are in the process of procuring the remaining required equipment Single Crystal, Fluorescence-Emission Spectroscopy ?Fluorescence spectroscopy complements the electronic absorption and Raman spectroscopy capabilities. The various options for light sources and detection instruments are under investigation. Significance ?The technologies we currently provide are unique in the United States, and will be enhanced further in the coming year. The scientific problems that we and our users will address are central to the progress of macromolecular sciences in the United States. The national resource we envision will support unprecedented, highly correlated studies. The results will provide much needed data on the complex relationships among macromolecular atomic structure, electronic structure and chemistry. These data will be used by the large number of national and international researchers in the field. Our plans will place the United States in a leadership position in this area.
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