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Copper vs. Molybdenum on a Dual Source System

AppNote SMX002: Comparison of Mo and Cu for single crystal X-ray diffraction


Since the introduction of CCD based area detectors for X-ray crystallography molybdenum has often been put forward as the best choice for a general purpose diffractometer system. The characteristics of molybdenum radiation, with its short wavelength and low absorption, made it a natural fit for the slower early CCD detectors and early software. However, the ever-growing popularity of dual source systems has enabled many chemical crystallographers to gain experience with copper as well as molybdenum sources. With recent advances in micro-focus source technology, detector technology and advanced data processing algorithms in Rigaku Oxford Diffraction’s CrysAlisPro software, copper is frequently a better alternative to molybdenum, and is therefore being increasingly used as the default X-ray source in many laboratories.

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