psd diffractometer
Department
Neutron Spectroscopy Research

Group leader: Zoltán Dudás

Group site: wigner.mta.hu/nanoszerkezet

Research activity of our group is based on neutron scattering studies performed on our four instruments, and also on experiments performed at foreign facilities.

External access to our facilities is regulated by the directives of the research infrastructures, and can be discussed by contacting the persons responsible for the individual instruments. The normal way of performing experiments is through experimental proposals.

Members of the group accomplished the development of an energy-selective neutron imaging set-up for the investigation of the cold neutron moderator of the  Budapest Research Reactor in the frame of the BrightnESS Horizon2020 project and participated in the design of a similar test beamline at ESS. The solid boron converter neutron detector developed at ESS has been thoroughly tested at Budapest.

Research on the methodology and applications of atomic resolution neutron holography has been continued. The local structure of a Sn single crystal with Cd impurities was reconstructed and the distortions of the crystal structure around the impurity atom was discussed. It was found that the effect of the different interatomic potential around the impurity atom have to be included beside the Friedel oscillation of the conduction electrons to fit the model to the measured distortions. For the first time, 3D displacements of atoms were measured showing the tendency of the local local structure changing to the white-tin phase stable at lower temperatures.

Alkyl and aryl substituted silica gels were synthesized and characterized using complementary physicochemical characterization methods. The silica host materials are designed to be proper host materials, for biomolecules or organic dyes, especially enzymes or porphyrins.

The researchers of the department take part in the design of the neutron guide system of the macromolecular time-of-flight neutron diffractometer (NMX) going to be built at the European Spallation Source (ESS) in Lund, Sweden. The NMX will be the first TOF protein neutron diffractometer in the world.