Yngve Cerenius

The crystallography beamline I711 at MAX II.

A new X-ray crystallographic beamline is operational at the MAX II synchrotron in Lund. The beamline has been in regular use since August 1998 and is used both for macro- and small molecule diffraction as well as powder diffraction experiments. The radiation source is a 1.8 T multipole wiggler. The beam is focused vertically by a bendable mirror and horizontally by an asymmetrically cut Si(111) monochromator. The wavelength range is 0.8-1.55 A with a measured flux at 1 A of more than 10(11) photons s(-1) in 0.3 mm x 0.3 mm at the sample position. The station is currently equipped with a Mar345 imaging plate, a Bruker Smart 1000 area CCD detector and a Huber imaging-plate Guinier camera. An ADSC 210 area CCD detector is planned to be installed during 2000.

A Series of Mixed‐Metal Borohydrides

Mix and match: A novel series of alkali-metal zinc borohydrides, LiZn 2(BH 4) 5 (see picture), NaZn 2(BH 4) 5, and NaZn(BH 4) 3, with fascinating structures are presented. An interpenetrated network structure, containing a [Zn 2(BH 4) 5] -. ion, is observed for the first time for a borohydride. A three-dimensional framework containing a polymeric [{Zn(BH 4) 3} n] n- ion is also identified.

Versatile in situ powder X-ray diffraction cells for solid–gas investigations

Two multipurpose sample cells of quartz (SiO2) or sapphire (Al2O3) capillaries, developed for the study of solid–gas reactions in dosing or flow mode, are presented. They allow fast change of pressure up to 100 or 300 bar (1 bar = 100 000 Pa) and can also handle solid–liquid–gas studies.

The yellow mini-hutch for SAXS experiments at MAX IV Laboratory

I911-SAXS is the new SAXS (Small-Angle-X-ray-Scattering) beamline at the MAX IV Laboratory in Lund, Sweden. It is one of the 5 stations of the hard X-ray Cassiopeia beamline (I911) at the 1.5 GeV ring MAX II. I911-4 was converted into a multipurpose SAXS station which opened to the scientific community in May 2011. The SAXS users community at this laboratory comes from diverse fields of research with different needs and requirements at the end-station. This results in different set-ups routinely being installed in the easy-accessible experimental mini-hutch. The beam can be focused at sample-to-detector distances between a few hundred millimetres and more than two meters. This versatility permits a selection of q-ranges between 0.006 A−1 and 2 A−1. The recent acquisition of a fast readout, low noise pixel detector (PILATUS 1M) and the implementation of a hight-throughput solution SAXS are the latest beamline upgrades.

Structure and morphology of wheat gluten films: from polymeric protein aggregates toward superstructure arrangements.

Evaluation of structure and morphology of extruded wheat gluten (WG) films showed WG protein assemblies elucidated on a range of length scales from nano (4.4 Å and 9 to 10 Å, up to 70 Å) to micro (10 μm). The presence of NaOH in WG films induced a tetragonal structure with unit cell parameters, a = 51.85 Å and c = 40.65 Å, whereas NH(4)OH resulted in a bidimensional hexagonal close-packed (HCP) structure with a lattice parameter of 70 Å. In the WG films with NH(4)OH, a highly polymerized protein pattern with intimately mixed glutenins and gliadins bounded through SH/SS interchange reactions was found. A large content of β-sheet structures was also found in these films, and the film structure was oriented in the extrusion direction. In conclusion, this study highlights complexities of the supramolecular structures and conformations of wheat gluten polymeric proteins in biofilms not previously reported for biobased materials.

Compressibility measurements on iridium

Abstract The compressibility of iridium was determined by energy-dispersive X-ray diffraction and synchrotron radiation up to a pressure of 65 GPa in the diamond-anvil cell. The bulk modulus ( B 0 ) was determined to be B 0 =306 (23) with B 0 ′=6.8 (1.5) when using a third order Birch–Murnaghan equation of state (B–M EoS). A distortion in the FCC structure of iridium was seen at pressures exceeding 59 GPa as additional diffraction peaks. These could be explained by the formation of a superlattice. By assuming hexagonal settings for a closed-packed structure it was determined to be a 14-layer closed-packed structure with cell parameters: a =2.60 and c =29.7 A at 65 GPa.

The new macromolecular crystallography stations at MAX-lab: The MAD station

A new beamline, Cassiopeia, at MAX II is about to come into operation. It consists of an energy‐tunable station and four side stations intended for macromolecular crystallography. The X‐ray source is a 3.5 T superconducting multipole wiggler installed in the 1.5 GeV MAX II storage ring. The energy‐tunable station use grazing incidence Rh‐coated silicon mirrors and an internally water‐cooled Si(111) double‐crystal monochromator while the four side stations use bent diamond and germanium monochromators and multilayer mirrors. This paper concentrates on the optics design of the energy‐tunable station and also briefly describes other beamline components.

Preliminary tests on the use of an acoustic levitator for liquid X-ray diffraction experiments

Some preliminary tests at the crystallography beamline I711 at the MAX II synchrotron in Lund, Sweden, have shown that it is possible to use acoustical levitation to keep a droplet of liquid and solid (powder) samples in an X-ray beam for a sufficient time for collection of the X-ray diffraction pattern.

Crystallography at MAX-lab

MAX-lab, the synchrotron radiation facility in Lund, Sweden is focused on soft X-ray activities. However, on the largest of the three storage rings, the 1.5 GeV MAX II ring, there are three beamlines operating at energies suitable for crystallographic experiments. I711 is a multipurpose beamline and is presently running powder diffraction and SAXS experiments. It is a tunable wavelength station with a range of 0.8-1.55 Å and uses a single monochromator crystal. The material science beamline I811 is primarily used for EXAFS and surface diffraction experiments and is a tunable wavelength station between 0.6-5 Å. It is equipped with a large multiple axis goniometer capable of carrying heavy loads such as UHV chambers. I911 is the protein crystallography beamline a consist of 2 fixed wavelength stations (0.97 and 1.03 Å) and one tunable wavelength MAD station (0.7-2.1 Å). The MAD station is equipped with a kappa goniostat and a MAR 225 CCD and the fixed wavelength stations has MARdtb goniostats with MAR 165 CCDs. The Mardtb on the 0.97 Å beamline has been redesigned to fit the MAR flatpanel. The three beamlines provide a very wide range of different setups and detectors ranging from the 430x350 mm flatpanel detector to scanning point detectors. A comparison of the stations and setups using powder diffraction data will be presented.