IµS-Mo for Small Molecule Crystallography

Diffraction experiments for routine structure determination show that the 30W IµS Classic for Mo-K_α radiation clearly outperforms standard Mo fine-focus sealed tube X-ray sources that were typically used in small molecule crystallography. It delivers 1.5 times the flux density of a 5 kW rotating anode plus graphite monochromator, at only 30 W. As he FWHM of the beam from IµS is about 110 µm, the IµS is the X-ray source of choice for small and challenging crystals. The IµS gives a three-fold intensity gain for very small crystals (edge length ≤ 0.1 mm). For medium sized crystals (edge length 0.1 —- 0.2 mm), the integrated intensity is comparable to that of a rotating anode generator with a graphite monochromator. Furthermore, the latest version of the IµS, the IµS^{High Brillance}, delivers 60% more intensity than the IµS Classic, thereby, clearly outperforming 5 kW rotating anodes. Therefore, the Mo IµS HB represents a very attractive low-maintenance and energy-saving alternative to rotating anode systems.

IµS-Ag for Material Science

The IµS for Ag radiation is the microfocus sealed tube X-ray source for single crystal and powder diffraction using short wavelength radiation. It either delivers a focused beam with a FWHM of 95 µm and a divergence of 5 mrad suitable for diffraction on single crystals, or a beam with a FWHM of about 155 µm and a divergence of 2.5 mrad suitable for diffraction experiments on smaller amounts of powder samples (e.g. in a diamond anvil cell).

The advantages of Ag radiation are the reduced absorption and extinction, and the „compression" of the reciprocal space. Thus, data are less biased by absorption and extinction, and access to a larger range of d-spacings at a fixed 2θ setting is gained. This is beneficial for high resolution diffraction experiments, such as studies on strongly absorbing inorganic solid state compounds or charge density measurements, and for high-pressure crystallography on single crystals and powder samples.