Appendix C - Specifications dated 03-13-2023.pdf

03/13/2023 Rev. 0 Appendix C – Specifications for X-Ray System

Necessary Capabilities Necessary Features Preferred features

1) Radiation Safety Enclosure

• Must meet all the regulations for radiation safety and safe operation procedure of Ames lab ESHA.

• Clearly visible lights to indicate X-ray status, such as X-ray on and shutter open.

• Safety interlocks.

• Well-illuminated interior with large windows for clear interior visibility.

• Sliding or swing doors to access the internal area.

• Must conform with the electrical safety requirements of the Ames lab.

• Windows minimum size at least half of the front panel.

2) X-ray generator • Maximum Power 65W or higher.

• Max. voltage >= 50 kV and current 1-2 mA.

• Stability: <= 0.1% per 8 hours after 30 minutes warm-up.

• Electric supply and safety features in conformity with Ames lab’s requirements.

• Instrument with the higher operating voltage and current are preferable.

3) Microfocus sealed X-ray tube with Ag anode

• High brilliance, high intensity with lifetime of >=3 years and warranty of 3 years or more (for tube and tube housing).

• Beam size at sample <= 120 microns

(FWHM).

• Air or internal liquid cooled with high temperature stability approx. ±0.01o C.

• Ag anode.

• Multilayer mirror focusing optics for Ag source for high brilliance.

• Components or optics, such as filters or monochromators, to monochromatize X-ray beam and significantly suppress K𝛽𝛽 for Ag anode.

• Supports continuous operation, infinitesimal intensity decay per year and no maintenance.

• Smaller beam size without a significant loss in intensity/flux is better for the pressure measurements and preferable.

• Higher intensity source with smaller beam size is preferred.

• Appropriate collimators with easy and error-free exchange.

4) Beam tubes with appropriate collimator at the end and a beam stop after the sample.

• • Beam stops and collimators with easy and precise exchange are preferable.

5) High speed 4-circle

Kappa or fixed-chi goniometer.

• Provides accurate and precise alignment of the sample with sphere of confusion < 7 micrometers.

• Large axis of rotation for kappa, phi (360o), omega and 2theta allowing measurements of large numbers peak for a complete refinement.

System with larger axis of rotation is preferable as it allows coverage of larger reciprocal space.

6) XYZ goniometer head for sample mounting

• It should be able to hold the larger weight of the diamond anvil pressure (weight of One20DAC) cells without any measurable wobble or tilts.

• Sample space (collision-free zone) after mounting high pressure kits should be large enough for the proper operations with our desired pressure cells. Tentative pressure cells are Diacell Bragg-mini, Bragg-S, Almax One20DAC, and symmetric DACs of DACTools (SSDAC70 and SSDAC80).

• Proof of the history of user’s using the larger-size pressure cells with large opening angle is a crucial requirement.

7) 2-dimensional array detector on a motorized track.

• A low-noise two-dimensional (array) detector with high sensitivity and dynamic range.

• Pixel size should be comparable with the beam spot for the better spatial resolution.

• Count rate of >1×106 counts/pixel-sec.

• Air-cooled.

• Detector on a rail that provides freedom of moving detector back and forth from the sample to adjust the resolution and angular coverage. Availability of computer controlled automatic movement is preferred.

• Warranty of at least a year but higher is preferable.

• Large dynamic range: 216 bits or higher is preferable.

• Large active area (at least 6000 mm2) is preferable.

• A shutterless feature for continuous acquisition thereby faster counting time and efficient measurements.

• Smallest readout (~ 3-14 ms;

standard mode; frame rate >=70 Hz) and dead time (~ 0) possible.

• Point spread function for a better resolution of closely spaced signals is preferable. This should be the case for the Ag anode.

• Large angular coverage: detector (2theta) movement >= 90 degrees on both sides is preferable.

• Efficiency of > 60% for X-ray from Ag anode is necessary but higher is preferable. Almost no parallax effects.

8) A Cooling system • An Oxford cryosystem for the measurements in temperature range of approx. 80 – 400 K (larger range preferable) with autorefill system.

• The unit should be complete with all necessary parts, such as cold head, 60-liter LN2 Dewar, transfer lines, controller and pumping units, cable, and adapters.

• Dry Air Unit and Line Drier.

• All necessary mounting to position the cryo nozzle easily and precisely for cooling during the data collection.

• Latest series (>= Cryostream 800 series) is preferable. Newest model in the series is preferred.

• Warranty of more than 1 year is preferable.

• Should be an integral part of the X-ray operating system.

• Warranty as provided by Oxford Cryosystems but should be at least of 1 year. Longer is preferable.

9) Telescope/camera with a monitor for sample viewing and alignment.

• Camera (telescope or video microscope) and monitor (inside the cabinet) for the sample viewing, initial alignment, and live image.

• Monitor should be clearly visible through the enclosure, with field of view >= 1.2 mm, and pixel in the millions.

• Demonstration of its successful usage both with and without DAC is necessary.

10) A dedicated computer for operation of the instruments.

• A computer dedicated for the instrument control with necessary tools/software for an experimental set up, data collection, data reduction and structure solution.

• Computer Components:

Latest OS (Windows 10 or higher) Intel core i7 or higher.

>= 256 GB SSD + 2TB hard disk drive.

RAM ~ 16 GB.

Keyboard and Mouse > 24” monitor.

EPEAT/EnergyStar certified

11) Programs, suite, and crystallographic software

• A comprehensive program/programs (software) for the experimental set-up, instrument control, data acquisition, data reduction, and structural refinement is required for our measurements on solid-state materials. This is required for both the measurements outside and inside the pressure cell.

• Remote control the X-ray system, cryosystem and temperature is preferable.

• Continuous check of the validity of the experimental setup or the safety monitoring by the software is necessary.

• Ability to run multiple data collections at multiple temperatures.

• User-friendly graphical user-interface along with the option of using the command line/scripts.

Preferred Capabilities:

1) High Pressure kits (exchangeable collimators and beam stops).

• High pressure kit (HPK) that allows the mounting of the diamond anvil cell with enough space necessary for the pressure measurements. Shorter collimator and longer beam stop to create more space for pressure cell are the components in HPK.

• Instrument with the diamond anvil pressure cell demonstrated data obtained at least in the range of 1-20 GPa.

• Will provide details of the necessary modifications to DAC vendors, (potential vendors- Almax and DacTools).

2) Proof that the system has been used for a pressure measurement on a solid-state material is necessary. A measurement using a diamond anvil cell on our materials is absolutely required.

3) Onsite initial application training and installation support. Also, guarantee continuous support for both the technical (hardware) and software at least for 5-7 years.

4) Option of dual anode sources so that lower energy anodes such as Mo can be added in future.

• Compatible with both single crystal and powder measurements.

• Preferable if it can handle modulated and twinned crystal structures.

• Has features including automatic structure solutions, unit cell determination, reduction of data into the format compatible for the refinement by third-party software like FullProf, GSAS, Jana, etc, data scaling and absorption correction, and background estimation.

• Multi-user, multi-site and free-of-charge for the upgrades.

• History of acquisition by institutions doing structural determination of the solid-state materials and demonstrated history of support, training, and upgrades.