Crystal samples for data collection at the CMCF should be prepared in compatible bases and containers. Since beamline CMCF-ID has an ISARA sample changer and CMCF-BM a Stanford Automated Mounting System (SAM) sample changer, there are slightly different container requirements which are described here.
The sample changers should be used whenever possible and require sample and container information in MxLIVE.
Bases and pins should be purchased, prepared and maintained with care. Pins that are not secure in their bases may slide out and interfere with the sample changer or cause centering problems. Rusted or bent sample mounts need to be avoided and debris and hardened glue should not be present on the outside of the bases or pins.
18 mm mounts are required when using the sample changers and strongly recommended. Plastic mounts should not be used.
The ISARA sample changer on CMCF-ID accepts only Universal Pucks (Uni-Pucks). The SAM sample changer on CMCF-BM accepts Uni-Pucks and SSRL-style cassettes. Please allow beamline staff to load containers into the sample changers for you. This is part of the beamline setup time and generally occurs during the first hour of your beamtime.
NOTE: Hampton Research Uni-Pucks labeled below 200 (eg: HR00199) are not compatible with the SAM automounter. If you have one of these pucks, please contact Hampton Research to exchange it.
Obtaining Mounts & Containers
Sample mounts and handling tools, Uni-Pucks and shipping dewars can be obtained through a number of suppliers, including MiTeGen, Crystal Positioning Systems, Molecular Dimensions and Hampton Research. If it is your first time using the Uni-Puck system, several of the companies offer Universal Puck starter kits containing the required accessories.
Although regular users are encouraged to invest in a set of Uni-Pucks and accessories, the CMCF has a limited supply available for lending. Please contact beamline staff to discuss borrowing items.
The Robotic Sample Handling Newsgroup & Information Forum maintains a list of containers & mounts supported by beamlines worldwide. Additional information is also maintained about the Uni-Puck Project. The SAM Hardware Page has detailed information about SSRL-Style Cassettes which can be used on CMCF-BM.
Powder Diffraction Samples
Powder diffraction experiments may be performed on the CMCF-BM beamline. Please discuss this with beamline staff during scheduling. In order for samples to be compatible with the beamline, they should be mounted on a compatible base into which is inserted an appropriate capillary, usually polyimide tubing, with the tip sealed with glue. In order for the capillary to not collide with beamline components, the total length from the bottom of the base to the tip of the capillary should not exceet 3.0 cm. The width of the capillary should not exceet approximately 1 mm. An acceptable example is shown below. Note that these samples are not appropriate for mounting with the automounter and training is needed for manual mounting on the beamline.
Use of any non-standard sample containers or mounts not described here must be discussed with beamline staff and described in your research Proposal. If approved, the beamline configuration may need to be adjusted. In such cases, additional resource and scheduling considerations may be required.