College of Chemistry X-ray Crystallographic Facility
The main funtion of CHEXRAY is to collect data on single crystals and solve and report their structure. RATES vary depending on what particular service is required.
Crystal evaluation and consultation on crystallization techniques are free during regular hours. Crystal samples are normally brought to Dr. Hollander for evaluation, but we will gladly perform laboratory visits to consult with users or to view crystals in situ. Crystal evaluation includes optical inspection for quality and size. If you have any doubts about your crystalline sample, bring it in! Even if most of your sample is below standard, it only takes one small fragment to obtain the structure. (Acceptable sample sizes vary from 0.05 mm to 0.3 mm in diameter, but very thin plates or needles may also be acceptable.) The structure analysis can be carried out as soon as a signed service work-order is obtained and a diffractometer is available. The results of the analysis are informally available within a day after data collection and the formal report is generally received within two weeks.
CHEXRAY will accept crystals from sources outside of the University. However, the University of California is a non-profit organization and as such we do not compete with private industry. Before contacting us you are encouraged to seek these services from a commercial laboratory, if such exists. If you have any questions regarding this policy or questions about sample analyses please call Dr. Hollander at 510-642-8444.
Students (and post doctoral fellows and faculty) can become authorized users of CHEXRAY equipment by successfully completing CHEM 208, the hands-on X-ray Crystallography course taught each spring semester. People with previous X-ray crystallographic experience (or those willing to study independently) may also become authorized users by informal examination by Dr. Hollander and successful performance of a crystal structure under his supervision. Authorized users are allowed to perform structures on their own, with advice and help available from the crystallographer. A signed user work-order is needed prior to data collection.
General use accounts are also available on the CHEXRAY computers at a nominal cost. These are intended for groups with crystallographic interests other than single-crystal structure determination or for groups with non-critical, light computer usage which will not interfere with the crystallographic use of the computers. If you have need for power computing, you should contact Dr. Kathy Durkin at the Graphics Facility for advice.
The facility maintains a current version of the Cambridge Structural Data base. This service is free of charge to students, faculty and staff of the College of Chemistry at U.C. Berkeley.
This facility is not available for Powder Diffraction
use. For information regarding powder diffraction contact the Stacy or
Gin groups.