Introduction

Femtosecond X-ray-induced fragmentation of fullerenes

“…Coherent diffractive imaging at the atomic level requires very short, intense x-ray pulses delivered effectively by free electron lasers (FEL) to record the diffraction pattern from biological molecules before they explode due to massive Coulomb explosion (32,33,(40)(41)(42). This bio-imaging has been demonstrated with resolution of tens of nanometers (43), but atomic resolution will require the understanding of ultrafast multiphoton ionization dynamics from inner shells which can be very well studied by atomic and molecular spectroscopic methodologies (11,14,28,30,31).…”

Solving protein nanocrystals by cryo-EM diffraction: Multiple scattering artifacts

“…This way, when the charge density maps were obtained with the erroneous intensities, we could identify the percentage error beyond which, the real-space charge density information starts to be substantially different from ideal. X-ray diffraction intensities and phases for lysozyme were obtained from 4ET8.pdb [23]. Keeping the phases unchanged, we introduced random errors to the intensities.…”

“…The high tolerance to error in diffracted intensities (a 40% error in |F| corresponds to almost 100% error in diffracted intensity) is a consequence of the inherently greater phase dependence of charge density maps. Although this seems to suggest an advantage in using TED, with its high tolerance to error in intensities, it emphasizes the necessity of accurate phase information (for which one is dependent on prior experiments [23]). (iv) R-factor analysis over a subset of simulated diffracted beams show that the maximum crystal thickness, for perfectly ordered protein crystals, that can be used to maintain a reasonable value (Ro0.3) is about 1000 Å.…”

Detector Development for the Linac Coherent Light Source

“…4, 2014 are difficult to crystallize. During the initial development phase, proteins with known structure have been used to carry out the experiments [14][15][16][17][18]. Recently, Barends et al [19] were able to perform singlewavelength anomalous diffraction (SAD) measurements, obtaining high-quality data from which a protein structure was determined de novo; that is, without previous knowledge of the structure.…”