Multi-Angle X-ray Scattering Facility

Location: LRSM Building
Supervisor/Coordinator: Prof. P. A. Heiney, Physics & Prof. Karen Winey, MSE

Prof. P. A. Heiney | heiney@sas.upenn.edu Prof. Karen Winey winey@seas.upenn.edu


Available Angular Ranges | Access | User Schedule | Representative Data

The multi-angle x-ray diffractometer system (MAXS) incorporates a high-brightness rotating-anode x-ray generator, focusing optics, and a two-dimensional detector. The Bruker Nonius FR591 rotating-anode x-ray generator together with Osmic Max-Flux optics and pinhole collimation produce a bright, highly collimated beam. A Bruker Hi-Star multiwire detector provides highly sensitive area detection with very low dark current. An integral vacuum is maintained between the generator and the detector. This arrangement substantially reduces both attenuation and small-angle scattering by air and windows. An entire diffraction pattern from a liquid crystal or polymer can be measured in several minutes, to be compared with the hours required for a conventional triple-axis, single-channel diffractometer. The MAXS system incorporates four fixed positions for sample placement, corresponding to different ranges of probed d-spacing. See table below for details. A temperature control stage can be mounted in any of the three fixed positions. It provides temperature control to better than 0.1 C in the range 0-300 C. A variety of specimen holders are available to readily mount samples in a transmission geometry. The specimen holders can accommodate capillaries (powders or fluids), fibers, gels, and films.

For videos, prepared by Paul Heiney, that provide an introduction to modern techniques of X-ray diffraction, please visit the X-Ray Scattering Lecture Series page hosted by the Penn’s ScholarlyCommons.

Available Angular Ranges

Configuration Sample to  Detector Distance d-spacing Range  (angstroms) Scattering Angle  (2 theta)  Range (degrees) Momentum Transfer  (q)  Range (Inverse Angstroms)
Small Angle 150cm 45 – 900 0.1 – 2.0 0.007 – 0.14
Intermediate Angle 54 cm 17-300 0.3 – 5.4 0.02-0.38
Wide Angle 11cm 3.9-60 1.4-24 0.1-1.6
Very Wide Angle 7cm 2.6-40 4-33 0.15-2.4

 

 

Equipment

Multi-Angle X-ray Scattering FacilityFrom left to right: generator, confocal optic, pinholes, small-angle, intermediate-angle, and wide-angle chambers.

Access

This facility is free to members of the Penn community; interested users can either collaborate with the faculty supervisors or be trained to use the instrumentation themselves. Other users are welcome to use the facility subject to availability. For academic users performing nonproprietary research, the rates are $30/hour or $400/day; for nonacademic users the rates are $200/hour or $1200/day. Additional charges for expert support should be discussed with Profs. Heiney or Winey.  

Location

The Multi-Angle X-ray Scattering Facility is located in room 119 of the Laboratory for Research on the Structure of Matter at the University of Pennsylvania . It is jointly supervised by Prof. Paul A. Heiney Department of Physics and Astronomy , and Prof. Karen Winey, Department of Materials Science and Engineering.  

Schedule

The user schedule for theLRSM Multiple-Angle X-ray Scattering facility can be accessed here: http://www.physics.upenn.edu/~heiney/xraysched.html  

Representative Data

Powder diffraction pattern

Powder diffraction pattern from a dendrimers self-assembled in the Pm-3n cubic phase.

Fiber diffraction pattern

Fiber diffraction pattern from dendrimers self-assembled in a columnar hexagonal phase with helical correlations.

Wide angle diffraction pattern

Wide angle diffraction pattern from uniaxially stretched polyurethane film.

Small angle scattering patterns

Small angle scattering patterns from carbide-derived porous carbons as a function of chlorination temperature, providing quantitative information on the size distribution of pore sizes.