The checkCIF output highlights the missed symmetry, as well as the high R int and final R values, and should alert the nonspecialist to the fact that there is a problem. Thus, the symmetry-equivalent reflections do not match, the Laue check fails and the larger centred unit cell is not identified. For the third experiment, the crystal is sufficiently far from the centre of the mount that it is precessing in and out of the beam. The first two experiments have similar data, both of which are perfectly acceptable for publication: a slight increase in R1, wR2 and goodness of fit (GooF) for the second experiment suggests the overall data quality is slightly worse, and the experiment took longer. Table 1 in the supplementary information summarizes the data. Three experiments were run with the crystal intentionally placed in the following positions: (i) correctly in the middle of the mount, (ii) incorrectly below the centre of the mount and (iii) incorrectly to the side of the centre of the mount. The effect of sample misalignment on the overall data quality and success of the instrument has been investigated with a crystal (0.24 Г— 0.28 Г— 0.29вЂ…mm) of dibenzyl sulfone, (1), for which a crystal structure had been previously reported by Rudolph et al. Herein, we discuss our experiences with the Bruker SMART X2S, presenting data for a representative range of chemical samples, highlighting its successes and challenges.Д¬orrect sample alignment remains critical for good quality diffraction data (MГјller, 2009 в–¶) and is a major consideration for any automated process. The use of CCD detectors for X-ray diffraction is a mature technology (Gruner et al., 2002 в–¶), with an air-cooled detector available since 2006. The main features are the air-cooled Breeze CCD detector and an Mo microfocus source. The design has centred not only on automatic data collection, structure solution and refinement, but also on some critical analysis of the structural results obtained. The Bruker SMART X2S is a benchtop crystallography instrument designed to enable more widespread use of crystallography in the wider chemical community, in the same way that NMR and mass spectrometry have become commonplace.

A criticism is that it leads to a вЂblack boxвЂ™ philosophy, characterized by noncritical appraisal of, and over-reliance on, the results obtained. Automation can increase awareness of a technique, but can also lead to reduced understanding and knowledge of the scientific theory involved and reduced appreciation of its difficulties or limitations. Automation is developing for both chemical and biological crystallography (Adams et al., 2010 в–¶ Dolomanov et al., 2009 в–¶ Fuller et al., 2010 в–¶). Chemical crystallography is a mature science in which structural analysis of well formed single crystals is routine for many samples (Ooi, 2010 в–¶), with the largest amount of time spent on problematic cases, such as twinning, disorder etc.

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