A structure determination was performed for the Berry research group on the compound that resulted from the reaction:
The crystal was a very good quality crystal so it was decided to collect data using a rapid, low resolution data collection mode in order to assess the effectiveness of rapid data collection. The "normal" high resolution mode uses a pixel density of 1900 x 1900 and requires 500 seconds for reading of the image plate. The low resolution mode uses a 950 x 950 pixel image plate which is read in 250 seconds, thus decreasing the data collection time by a factor of approximarely two for data collections with exposure times less than 250 sec. Below are image plate pictures from the R-AXIS data collection using Moly radiation. The image plate is 200 x 200 mm in size and the crystal to plate distance was 70 mm. This leads to a max 2q of 55° (resolution=0.77Å). The oscillation angle was 6° and the exposure time was 100 sec. On the left is the full scale image plate and on the right a "zoomed" view of the indicated area.
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The crystal was mounted on the R-AXIS at 9:05 A.M.; the unit cell was determined by 9:45 (orthorhombic, P212121, a=16.8374(5), b=17.9722(3), c=9.0782(3) Å) and a strategy for data collection was devised. By 10:30 approximately 90% of an asymmetric unit of data had been measured (6 frames) at which time the data were processed and the structure was solved (at 10:50). The data collection was completed at 11:30. A total of 20942 reflections were measured, leading to 6165 unique reflections (Rint=0.0501). Least squares refinement (SHELXL-93) converged to R1=0.0403 (for refs with F2 > 2 s) and wR2=0.0868. The data were "good enough" to permit the location and refinement of the hydride hydrogen and to successfully refine a model for rotational disorder of one of the PMe3 groups (P3-C7-C8-C9). A subsequent data collection using the slower high resolution mode resulted in R1=0.0392 and wR2 =0.0955. Below is a comparison of the refined bond distances resulting from the "slow" data collection and the "fast" data collection:
Below is a chemsymphony representation of the molecule which can be rotated in real time and an ORTEP:
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