X-ray photon-in/photon-out methods for chemical imaging
Most interesting materials in nature are heterogeneous, so it is useful to have analytical techniques with spatial resolution sufficient to resolve these heterogeneities. This article presents the basics of X-ray photon-in/photon-out chemical imaging. This family of methods allows one to derive images reflecting the chemical state of a given element in a complex sample, at micron or deep sub-micron scale. X-ray chemical imaging is relatively non-destructive and element-selective, and requires minimal sample preparation. The article presents the basic concepts and some considerations of data taking and data analysis, along with some examples.