Goniometer, single crystal X-ray diffraction

Sphere of confusion - What´s the difference?

Bruker Goniometer (FIXED-CHI or KAPPA)

Goniometer Diffusion, SC-XRD
Small sphere of confusion of a Bruker Goniometer

Our D8 goniometer is designed for the highest accuracy and precision, superb alignment, and long-term reliability. Our goniometer has the smallest error in intersection of the instrument axes, provides the best sphere of confusion, and is unsurpassed by any other goniometer. Even the tiniest microcrystal stays reliably centered during the entire data acquisition, guaranteeing the best possible structure.

Non-Bruker Goniometer

Standard Goniometer Diffusion, SC-XRD
Large Sphere of confusion of a non-Bruker Goniometer

A large sphere of confusion is a serious problem for large crystals because the scattering volume significantly fluctuates. Tiny crystals may even move out of the beam completely. The smaller the beam, the more pronounced this problem becomes. This inhibits proper scaling and absorption correction, and results in systematically poor structures.

More info

Read more on Bruker´s FIXED-CHI Goniometer or KAPPA Goniometer