The thematic "dynamics" addresses time dependent phenomena, such as biological processes, motion of biomolecules and colloids, or transport processes in hard matter, utilizing the accessible time and length scales with neutrons and X-rays, and the coherent properties of MAX IV. Systems and processes studied include equilibrium as well as non-equilibrium phenomena, reversible and irreversible processes, order-disorder transitions, dynamics on different length and time scales, as well as transient states that could for example be studied with pump-probe experiments. We focus in particular on the application and future development of experimental tools such as quasi-elastic neutron scattering (for example neutron spin echo or backscattering experiments), x-ray photon correlation spectroscopy or fast pump probe experiments, and computer simulations performed in order to help und understand experimental data.
HAPPENING IN DYNAMICS
DYNAMICS WG 1
DYNAMICS OF BIOLOGICAL MACROMOLECULES
The working group will address the need to educate future users of ESS, MAX IV and other major research infrastructures in topics related to dynamics of biological macromolecules. We bring together leading scientists from soft matter physics, biology and pharmaceutical sciences, with expertise in experiments, theory and computer simulations and showcase what can be achieved at MAX IV and synchrotrons worldwide.
DYNAMICS WG 2
X-ray Photon Correlation Spectroscopy
Description WG XRPCS
DYNAMICS WG 3
Dynamics of Membranes and their Constituents
Recent years have seen strong research efforts on the lipid component of biological membranes. While many studies have been focused on the membrane structure, the dynamics of such systems are crucial for the function of the membrane including membrane bound proteins.
The relevant time scales are wide, from seconds to nanoseconds, and therefore a combination of techniques and modeling tools are requires. To some extent and for longer timescales ”traditional” neutron and x-ray scattering techniques can be used. However this often requires a particular sample environment like stopped-flow set-up or temperature and pressure jumps.
Inelastic neutron scattering techniques and X-ray Photon Correlation Spectroscopy (XPCS) has emerged as promising techniques, which will particularly benefit from the new powerful neutron and synchrotron facilities, ESS and Max IV, built up in Lund.
This will be particularly useful for membrane dynamics studies. Increasingly, synchrotron and neutron users as well as large scale facilities have realised the strength of combining large-scale facilities techniques with lab instruments. This includes fluorescence, NMR, surface chemistry techniques and light scattering. They do not only allow better planning of experiments at the large scale facilities, but also provide complementary information that sometimes are essential for the evaluation of neutron and synchrotron x-ray and neutron data.
The development of coarse graining strategies and other modeling tools has allowed us to develop relevant in silico models of the dynamics of rather complex membranes. Although these simulation have given us insight on the dynamics, the combination with in particular Quasielastic neutron scattering (QENS) and other inelastic neutron scattering techniques such as neutron spin-echo with modeling have emerged as powerful tool box do study dynamics in life science systems. The experimental studies will give the needed relevant parameters for the simulations and inversely the simulations will help interpret the experimental data. It is clear that neutron and synchrotron x-ray techniques are powerful techniques to study dynamics in biomembrane systems.
DYNAMICS WG 4
Scattering and dynamics of Flowing Soft Materials
Soft matter is a convenient term encompassing a wide range of materials, such as polymers, surfactants, colloids, emulsions, liquid crystals and various biological materials. These diverse materials may exhibit time-dependent structures under transient or out-of-equilibrium conditions resulting from for example self-assembly processes, phase transitions or in response to external fields, such as flow. These time-dependent or flow-dependent structures may in turn influence their viscoelastic behavior or vice versa and be triggered by instabilities. Shear and extensional flow fields are ubiquitous in the manufacture, processing and use of these everyday materials and yet, typical experimental techniques, like small angle scattering, only provide information about the quiescent or time-averaged state. The combination of new time- and spatial-resolved experimental methods combined with computational and theoretical approaches is required to determine the complex nonlinear and time-varying response to deformations which is often also non-homogeneous. Thus, the study of flowing soft matter presents new opportunities and challenges of great scientific and technological interest carving out the path for new discoveries and innovations of flowing soft materials.