May 2014 Archives

Lecture Date: Tuesday May 27, 2014. Dr. Johanna Nelson Weker, SLAC, delivered the SLAC public lecture, "X-rays Reveal Secret Life of Batteries" (https://www.youtube.com/watch?v=V8lSTLRkKEk)

At ESRF in Grenoble, France, several very interesting imaging experiments are going on. Some fossils of Archaeopteryx, which were believed to live 150 million years ago, are being imaged by using a pin-hole X-ray camera at synchrotron beamlines BM5 and ID19. The main question is about their wings - whether they could fly or not. So far, the research has encountered a number of challenges. The project is conducted by Germany's Burgermeister-Muller-Museum (the Solnhofen Museum). For more information, see the following Web site, http://www.solnhofen.de/index.php?id=0,49

The use of X-ray free-electrons has enabled plenty of fascinating science, such as watching non-equilibrium excited-state dynamics in complexes of 3d transition metals. Scientists at LCLS, Stanford have performed femtosecond resolution X-ray fluorescence spectroscopy, with its sensitivity to spin state, elucidating the spin crossover dynamics of [Fe(2, 2ˈ-bipyridine)₃]²⁺ on photoinduced metal-to-ligand charge transfer excitation. For more information, see the paper, "Tracking excited-state charge and spin dynamics in iron coordination complexes", W. Zhang et al., Nature, 509, 345 (2014).