ABSTRACT: This talk will describe the X-ray liquid surface scattering instrument at the Open Platform and Liquid Surfaces (OPLS) at NSLS-II (Brookhaven National Laboratory) which is one of two endstations at the Soft Matter Interfaces (SMI) beamline (12-ID). OPLS shares the photon delivery optics with the downstream SWAXS endstation (double crystal silicon monochromator & horizontal mirror) in a time-shared mode where the OPLS instrument gets about 30% of the available time. OPLS usually operates at 14.4 keV but other energies between 8-24keV are possible. To deflect the beam downward, the instrument uses a single, asymmetric cut Ge (111) crystal. Vertical focus (> 6 μm) is provided by multiple Diamond CRLs located 2m from the sample where the typical beam size is 13 μm by 0.5 mm at 14.4 keV. Four 2D X-ray detectors are mounted on the sample 2-theta scattering arm (air pad supported) located downstream of the sample. These detectors support a variety of X-ray techniques including X-ray reflectivity (GaAs Lambda 256k), Grazing Incidence Small-Angle X-ray Scattering (Pilatus 1M) and direct Wide-Angle X-ray Scattering (Pilatus 300k) and with Soller Slits (Pilatus 100k). A Langmuir Trough and a small chamber holding up to 3 small troughs with two pressure sensors are also available. The endstation is controlled by Bluesky, a versatile, python-based control software program developed at NSLS-II.
In addition to describing the instrument [1], early results from user and BNL science will be presented.
Acknowledgement: This research used SMI-OPLS of the National Synchrotron Light Source II, a U.S. Department of Energy Office of Science User Facility operated for the Department of Energy (DOE) Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704.
REFERENCES:
[1] D. M. Bacescu, L. Berman, S. Hulbert, B. Ocko, and Z. Yin, “A New Experimental Station for Liquid Interface X-Ray Scattering At NSLS-II Beamline 12-ID”, in Proc. 11th Mechanical Engineering Design of Synchrotron Radiation Equipment and Instrumentation Conf. (MEDSI'20), Chicago, USA, Jul. 2021, pp. 330.