Chemical Crystallography

IμS with Silver Radiation

Beam profile of the IμS with a silver tube
Beam profile of the IμS

The APEX II QUAZAR features the world’s first microfocus source available with a silver tube. This IμS is combined with the specially designed QUAZAR multilayer optics. Compared to a conventional sealed tube system a one order of magnitude higher flux density of 3 x 109 X-rays/(s mm2) becomes accessible.

The characteristic wavelength (0.56083 Å) of the silver target is the shortest wavelength available for in-house systems. The use of silver radiation opens the possibility for high-end investigations of challenging samples particularly in the fields of mineralogy and solid-state chemistry. Silver radiation allows the collection of data to 30% higher resolution and at the same time minimizes absorption effects.

More applications

  • High-pressure studies usually suffer from the limiting opening angle of the conventionally used diamond-anvil cells (DAC). Due to the smaller beam size and the smaller volume illuminated by the source unwanted diffraction signals from the diamonds and the cell itself are much less pronounced.
  • Charge density studies take advantage of the high resolution which can be obtained while at same time absorption effects are greatly reduced, which makes an accurate correction much more straight forward and more accurate.
  • Very strong absorption can severely hamper the structure determination using Mo-radiation. Ag-radiation greatly facilitates absorption correction in these cases.