Almost 50 years have passed since the famous papers of Hugo Rietveld from the late sixties where he describes a method for the refinement of crystal structures from neutron powder diffraction data. Soon after, the potential of the method for laboratory X-ray powder diffraction was discovered. Although the method is now widely accepted, there are still many pitfalls in the theoretical understanding and in practical daily use. This book closes the gap with a theoretical introduction for each chapter followed by a practical approach.The flexible macro type language of the Topas Rietveld software can be considered as the defacto standard.
Almost 50 years have passed since the famous papers of Hugo Rietveld from the late sixties where he describes a method for the refinement of crystal structures from neutron powder diffraction data. Soon after, the potential of the method for laboratory X-ray powder diffraction was discovered. Although the method is now widely accepted, there are still many pitfalls in the theoretical understanding and in practical daily use. This book closes the gap with a theoretical introduction for each chapter followed by a practical approach. The flexible macro type language of the Topas Rietveld software can be considered as the defacto standard.
Andreas Potschka discusses a direct multiple shooting method for dynamic optimization problems constrained by nonlinear, possibly time-periodic, parabolic partial differential equations. In contrast to indirect methods, this approach automatically computes adjoint derivatives without requiring the user to formulate adjoint equations, which can be time-consuming and error-prone. The author describes and analyzes in detail a globalized inexact Sequential Quadratic Programming method that exploits the mathematical structures of this approach and problem class for fast numerical performance. The book features applications, including results for a real-world chemical engineering separation problem.
Magnetic Small-Angle Neutron Scattering provides the first extensive treatment of magnetic small-angle neutron scattering (SANS). The theoretical background required to compute magnetic SANS cross sections and correlation functions related to long-wavelength magnetization structures is laidout. The concepts are scrutinized based on the discussion of experimental neutron data. Regarding prior background knowledge, some familiarity with the basic magnetic interactions and phenomena as well as scattering theory is desired.Besides exposing the different origins of magnetic SANS, and furnishing the basics of the magnetic SANS technique in early chapters, a large part of the book is devoted to a comprehensive treatment of the continuum theory of micromagnetics, as it is relevant for the study of the elastic magneticSANS cross section. Analytical expressions for the magnetization Fourier components allow to highlight the essential features of magnetic SANS and to analyze experimental data both in reciprocal, as well as in real space. Later chapters provide an overview on the magnetic SANS of nanoparticles andso-called complex systems (e.g., ferrofluids, magnetic steels, spin glasses and amorphous magnets). It is this subfield where major progress is expected to be made in the coming years, mainly via the increased usage of numerical micromagnetic simulations (Chapter 7), which is a very promisingapproach for the understanding of the magnetic SANS from systems exhibiting nanoscale spin inhomogeneity.
Thank you for visiting our website. Would you like to provide feedback on how we could improve your experience?
This site does not use any third party cookies with one exception — it uses cookies from Google to deliver its services and to analyze traffic.Learn More.