CS contains a sign error. The corrected Table is given below:| Phys. Chem. Chem. Phys., 2007, 9 | |
Additions and corrections First-principles calculations of solid-state 17O and 29Si NMR spectra of Mg2SiO4 polymorphs |
Sharon E. Ashbrook, Laurent Le Pollès, Chris J. Pickard, Andrew J. Berry, Stephen Wimperis and Ian Farnan
Phys. Chem. Chem. Phys., 2007, 9, 1587 (DOI: 10.1039/b618211a). Amendment published 20th September 2007
In Table 1 of this recent paper, the column headed CS contains a sign error. The corrected Table is given below:
Table
1 Experimental and calculated 29Si shielding parameters (isotropic chemical shift ( iso), anisotropy (CS), asymmetry ( CS) and principal tensor components (11, 22 and 33 expressed as deshieldings in order of decreasing ppm)) for  -Mg2SiO4(forsterite) | ||||||
| iso/ppm a
|
CS/ppm
| CS
| 11/ppm
| 22/ppm
| 33/ppm
|
|
| CASTEP (Brown37) | –62.7 | 23.6 | 0.88 | –40.6 | –61.4 | –86.4 |
| CASTEP geometry optimized (Brown37) | –62.0a | 29.3 | 0.61 | –38.3 | –56.4 | –91.3 |
| CASTEP (Hazen36) | –62.4 | 31.1 | 0.62 | –37.3 | –56.5 | –93.4 |
| Single-crystal NMR14 | –63.2 | 32.2 | 0.51 | –38.8 | –55.3 | –95.4 |
| Static NMR | –62.1 | 32.3 | 0.57 | –37.8 | –55.2 | –94.5 |
| MAS NMR13 | –61.9 | |||||
| a For CASTEP calculations iso has been set to –62.0 ppm for the structure produced after geometry optimization and other values referenced relative to this. |
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The original error also necessitates small corrections to Figures 2 and 8, given below:
![[correct version of Fig. 2]](b618211a-f2.gif) |
||
Fig. 2 (a)29Si (99.3 MHz) NMR spectrum of a static sample of forsterite, recorded using a spin-echo pulse sequence, where 144 transients were averaged with a recycle interval of 1200 s. The sample was packed in a 4-mm rotor and a radiofrequency field strength,  1/2 , of 56 kHz was employed. Also shown are lineshapes simulated using principal tensor components from CASTEP calculations for the structures of Brown37 (b) before and (c) after geometry optimization, and (d) Hazen.36 | ||
![[correct version of Fig. 8]](b618211a-f8.gif) |
||
| Fig. 8 Comparison of calculated and experimental 29Si CS and CS for forsterite (-Mg2SiO4). Calculated results are shown for the structures of Brown before (filled diamond) and after (diamond) optimization (Brown*) and Hazen (filled square). Experimental results from static powders (cross) and single-crystal work14 (star) are also shown. | ||
The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.