Characterization of Picoscale 3D Local Atomic Structure of Nanomaterials by High Energy Resolution Synchrotron Based XANES Spectroscopy
The study of nanoscale atomic structure of matter is important both from fundamental point of view for the understanding the nature of physical and chemical properties of the materials and for applied research as a basis for the synthesis of novel nanomaterials with necessary properties, for example, advanced nanocatalysts based on metal clusters functionalized MOF and zeolite class family materials. To gain deep insight into the nature of the relation “structure-function” one has to use both computer nanodesign and advanced experimental methods for nanodiagnostics. The status of modern theoretical analysis of the experimental x-ray absorption spectra to extract structural parameters is presented.
Novel in-situ technique for picoscale characterization - extracting of 3D local atomic structure parameters on the basis of advanced quantitative analysis of X-ray absorption near edge structure (XANES) and high energy resolution XANES - has been developed. The possibility to extract information on bond angles and bond-lengths (with accuracy up to 1 pm) is demonstrated.
In the framework of these approaches the results of recent studies of local atomic structure for several types of advanced nanomaterials are reported. The nowadays progress in the development of the synchrotron radiation facilities for time dependent measurements opened the possibilities for the study the atomic and electronic structure dynamics as well. The specific feature of the method is that it makes it possible not only determine with high precision the interatomic distances between the atoms in nanostructured materials without long range order, but also to estimate the angle distribution of atoms (chemical bond angles) and do all this for the processes lasting less than a nanosecond.