biostudies-literatureUnknown72(Pt 2)van Genderen EUntil recently, structure determination by transmission electron microscopy of beam-sensitive three-dimensional nanocrystals required electron diffraction tomography data collection at liquid-nitrogen temperature, in order to reduce radiation damage. Here it is shown that the novel Timepix detector combines a high dynamic range with a very high signal-to-noise ratio and single-electron sensitivity, enabling ab initio phasing of beam-sensitive organic compounds. Low-dose electron diffraction data (∼ 0.013 e(-) Å(-2) s(-1)) were collected at room temperature with the rotation method. It was ascertained that the data were of sufficient quality for structure solution using direct methods using software developed for X-ray crystallography (XDS, SHELX) and for electron crystallography (ADT3D/PETS, SIR2014).Acta crystallographica. Section A, Foundations and advances236-42https://www.ebi.ac.uk/biostudies/studies/S-EPMC4770873biostudies-literatureAb initio structure determination of nanocrystals of organic pharmaceutical compounds by electron diffraction at room temperature using a Timepix quantum area direct electron detector.PMC4770873Portillo QPannu NSvan Genderen EGruene TClabbers MTAbrahams JPStewart ANederlof INicolopoulos SDas PPBarentsen KCfalseAb initio structure determination of nanocrystals of organic pharmaceutical compounds by electron diffraction at room temperature using a Timepix quantum area direct electron detector.Until recently, structure determination by transmission electron microscopy of beam-sensitive three-dimensional nanocrystals required electron diffraction tomography data collection at liquid-nitrogen temperature, in order to reduce radiation damage. Here it is shown that the novel Timepix detector combines a high dynamic range with a very high signal-to-noise ratio and single-electron sensitivity, enabling ab initio phasing of beam-sensitive organic compounds. Low-dose electron diffraction data (∼ 0.013 e(-) Å(-2) s(-1)) were collected at room temperature with the rotation method. It was ascertained that the data were of sufficient quality for structure solution using direct methods using software developed for X-ray crystallography (XDS, SHELX) and for electron crystallography (ADT3D/PETS, SIR2014).2016-01-01T00:00:00Z2016 Mar2025-04-25T19:03:15.54Z2019-03-27T00:04:29ZS-EPMC47708732691937510.1107/S2053273315022500