X-ray Absorption Spectroscopy
X-ray absorption spectroscopy (XAS) is a well-established technique for simultaneous local geometric and electronic structure determination of a metalloprotein active site. XAS is element specific and sample state agnostic, making it ideal for dilute biological solutions. SSRL has three hard x-ray and two tender x-ray biological spectroscopy beamlines, together covering 2-30 KeV. The beamlines are equipped with specialized instrumentation, including low temperature (liq He) cryostats, solid-state Ge and Silicon drift detectors for dilute samples.
Beam Line 9-3
Beam line 9-3 is the side station on the hybrid wiggler beam line 9 dedicated to general user biological XAS. BL9-3 provides high intensity over a broad x-ray energy range, and is designed to provide focused beam with an energy range of 5 keV to 30 keV.
Beam Line 7-3
Beam line 7-3 is the side station on the wiggler beam line 7 dedicated to general user biological XAS. BL7-3 provides medium high intensity over a broad x-ray energy range, and is designed to provide unfocused beam with an energy range of 5 keV to 30 keV.
Beam Line 4-3
Beam line 4-3 is the side station on the wiggler beam line 4 dedicated to biological, environmental and chemical catalysis XAS. BL4-3 provides medium high intensity over a narrow x-ray energy range, and is designed for primarily for studies to the tender x-ray regime.
Beam Line 14-3a
Beam line 14-3a is the side station on the bending magnet beam line 14 dedicated to biological, environmental and chemical catalysis XAS. BL14-3a provides medium high intensity over a narrow x-ray energy range, and is designed for primarily for studies in the tender x-ray regime.
The SSRL SMB group is directly responsible for the maintenance and operation of the biological spectroscopy beamlines. User support is provided at the technical, engineering and scientific level of data acquisition and analysis by experienced staff personnel. See more.
The SMB group maintains and operates standard and specialized in-hutch instrumentation for a variety of research programs. These include; cryostats for low-temperature measurements, detector systems serving dilute and concentrated samples and specialized instrumentation for tender-energy and single-crystal XAS measurements. Experimental details about beamlines and information about their specific capabilities are listed under each beamlines technical page.
An interactive interface of the monochromotor crystal glitch library can be found here
The data collection softwares used on the spectroscopy beamlines include XASCollect and XASSCAN. Beamline computers are also equipped with the data analysis softwares EXAFSPAK and SixPACK.
The next steps after successful data measurement at the experimental station are data reduction, analysis and simulation. SSRL staff provides training and support for in-house data analysis software for preliminary data-analysis and the SMB group organizes annual Summer Schools for training in advanced experimental data analysis. In addition, several web-based resources are available for additional and specialized information.
The research conducted at the bio-spectroscopy beamlines follows the mission of NIH and DOE-BER and is aimed at elucidating the geometric and electronic structure of metalloprotein and cofactor active sites and biomimetic model complexes in order to shed light on the mechanistic aspects of relevant biological systems. High-impact publications from the bio-spectroscopy beamlines are routinely highlighted by SSRL. See more.