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Research Council grant EP/D052939/1.The CXD instrumentation,based at APS Phs.S1 atus Solidi A204.2542-2547(2007). beamline 34-ID-C,was built with US National Science Foundation grant DMR-9724294 37.Minkevich,A.A.et al.Inversion of the diffraction pattern from an and supported by the Materials Research Laboratory of the University of Illinois under inhomogeneously strained crystal using an iterative algorithm.Phys.Rev.B US Department of Energy(DOE)contract DEFGO2-91ER45439.The APS is operated by 76,104106(2007). the US DOE contract number W31 109 ENG 38. 298 NATURE MATERIALS|VOL 8|APRIL 2009 www.nature.com/naturematerials 2009 Macmillan Publishers Limited.All rights reserved298 nature materials | VOL 8 | APRIL 2009 | www.nature.com/naturematerials review articles | insight NaTure maTerials doi: 10.1038/nmat2400 12. Varela, M. et al. Materials characterization in the aberration corrected scanning transmission electron microscope. Annu. Rev. Mater. Res. 35, 539–569 (2005). 13. 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Vartanyants, I. A., Pitney, J. A., Libbert, J. L. & Robinson, I. K. Reconstruction of surface morphology from coherent X-ray reflectivity. Phys. Rev. B 55, 13193–13202 (1997). 62. Vartanyants, I. A. & Robinson, I. K. Partial coherence effects on the imaging of small crystals using coherent X-ray diffraction. J. Phys. Condens. Matter 13, 10593–10611 (2001). acknowledgements We acknowledge the collaboration of M. Watari, M. Newton, S. J. Leake, R. A. McKendry and G. Aeppli in the experimental work presented in Fig. 4. That previously unpublished research was supported by a Royal Society Wolfson Award, a European Seventh Framework Programme Advanced Grant and the Engineering and Physical Sciences Research Council grant EP/D052939/1. The CXD instrumentation, based at APS beamline 34-ID-C, was built with US National Science Foundation grant DMR-9724294 and supported by the Materials Research Laboratory of the University of Illinois under US Department of Energy (DOE) contract DEFG02-91ER45439. The APS is operated by the US DOE contract number W 31 109 ENG 38. nmat_2400_APR09.indd 298 13/3/09 12:04:33 © 2009 Macmillan Publishers Limited. All rights reserved