XtaLAB P200 overview

For the expert small molecule crystallographer, where a flexible configuration is required, Rigaku offers the XtaLAB P200 chemical crystallography system. The XtaLAB P200 represents the state-of-the-art in a chemical crystallography system with the DECTRIS PILATUS3 R 200K hybrid pixel array detector (HPAD), the very same technology CERN used to detect the putative Higgs boson. The XtaLAB P200 can be configured with molybdenum (Mo) radiation, copper (Cu) radiation, or a combination of the two. With a true photon counting detector, XtaLaB P200 is the perfect choice of X-ray diffractometer for both day-to-day routine crystal structure determinations and the more challenging high-resolution electron density studies.

Kappa goniometer

At the heart of the product is our AFC-Kappa goniometer, a design that benefits from over fifty years of precision engineering experience. The open geometry vastly simplifies crystal mounting, alignment and positioning of low temperature devices while providing superior coverage of reciprocal space, even in the presence of tertiary equipment. And free rotation about the Kappa-axis gives the AFC-Kappa more flexible positioning. However, depending on your requirements, a 4-axis partial χ goniometer and a 3-axis fixed χ goniometer are also available.

Choice of available X-ray sources

Inherent to the unique flexibility of this system is a choice of X-ray sources, ranging from: a high-frequency 3 kW sealed tube, to a MicroMax™-003 microfocus seal tube, to a 1.2 kW MicroMax-007 HF microfocus rotating anode and the industry leading 2.97 KW FR-X. Available optics range from a traditional graphite monochromator or high-performance SHINE™ optic to a VariMax™ confocal X-ray optic.
Advanced hybrid pixel detector array technology
The technology behind the PILATUS3 R 200K is dramatically different from what is used in phosphor-based CCD detectors and phosphor-based CMOS detectors. In phosphor-based detectors, X-rays are converted to light, which then travels through a glass stub or taper and finally reaches a CCD or CMOS chip where it is accumulated until read. The final step in the signal processing chain is an analog to digital conversion. Each step in the detection process adds to the noise of the signal and hurts the ability to measure weak signals.

With a hybrid pixel array detector, the X-rays are measured directly with a solid-state sensor. Each X-ray photon that hits the detector creates a large number of electron-hole pairs, with the charge being directly transferred to the CMOS chip and measured without the need for analog to digital conversion. Hybrid pixel array detectors feature very high dynamic range, extremely low noise, and hence achieve optimal signal-to-noise ratio at short readout time and high frame rates.

The benefits to the chemical crystallographer are very significant. The low-noise characteristics of the detector mean that the ability to measure weak reflections accurately is improved. This can be seen in the measurement of higher resolution reflections for weakly diffracting crystals. A PILATUS3 R 200K detector is the perfect device to optimally collect weak diffraction and improve the success of structure solution.

In addition to the outstanding low-noise characteristics, the PILATUS3 R 200K allows you to collect data very quickly without having a negative impact on your data quality. The PILATUS3 R 200K is a photon counting device, which means it does not integrate photons before being readout. There is essentially no deadtime during readout so the most efficient way to collect data is to open the shutter, spin the crystal and measure data. Each time the shutter is opened and closed and each time the oscillation axis is started and stopped, there is some error introduced into the data. Shutterless data collection removes those errors as well as removing the deadtime from the experiment. The result is better quality data in a shorter period of time.