The Barbour Group - University of Stellenbosch

OVERVIEW OF OUR FACILITIES

Laboratories: Our lab is located in the De Beers Building on the main campus of Stellenbosch University. We occupy five instrumentation laboratories as well as a large synthetic laboratory with 12 fume hoods. Standard equipment includes vacuum pumps, balances, chemical cabinets, programmable ovens, rotary evaporators, solvent stills, drying ovens, refrigerators, etc. We also keep a large range of modular items (digital and analogue video cameras, temperature controllers, zoom microscopes, optical bench, motion controllers, Swagelok gas fittings, pressure transmitters, etc.) that we use to assemble apparatus for various non-standard experiments.

Office space: We have 20 desks for students and postdocs, 3 networked printers, a kitchen and a small meeting room.

Software: We have a site license for the Cambridge Crystallographic Database. We also have licenses for TOPAS and Materials Studio.

Computing: Each member of the group is supplied with a high-end notebook or desktop computer. We also have access to the Centre for High-Performance Computing and a 1023-node cluster housed in Electrical Engineering for CPU-intensive computational studies.

Workshop: Our research frequently involves the development of new instruments/devices and customisation of existing equipment. We therefore maintain our own workshop facilities for basic operations that we can accomplish ourselves. However, we also have access to the Science Faculty Workshop for more advanced metal work. The group's workshop houses a range of metalworking tools, including two lathes, a milling machine, drill presses, TIG welder, etc.). A section of the workshop is reserved for electronics and we keep stock of the most commonly-used components. Another section of the workshop is reserved for the assembly and modification of gas-reticulated systems and we keep a large stock of Swagelok components, pressure transducers, regulators, etc.

Glassblowing: We have easy access to a full-time glassblower within the Department of Chemistry and Polymer Science.

Additional resources: Apart from the instrumentation in our own research space, we have access to all of the specialised instrumentation managed by the Central Analytical Facility of the University of Stellenbosch.

X-RAY DIFFRACTION


Bruker Venture single-crystal X-ray diffractometer Managed by Leigh Loots Kappa 4-circle goniometer Incoatec IμS microfocus Mo source (3rd generation) Photon-2 CMOS detector Oxford Cryosystems Cryostream 800+ cryostat (80-500 K).

Bruker Apex-2 Duo single-crystal X-ray diffractometer Managed by Leigh Loots 3-circle platform goniometer Incoatec IμS microfocus Mo source Incoatec IμS microfocus Cu source Apex-2 CCD detector Oxford Cryosystems Cryostream 700+ cryostat (80-500 K).

Bruker Smart Apex-2 single-crystal X-ray diffractometer Managed by Leigh Loots 3-circle platform goniometer Incoatec IμS microfocus Mo source (2nd generation) Apex-2 CCD detector Oxford Cryosystems Cryostream 700+ cryostat (80-500 K).

PANalytical X'Pert Pro MPD powder diffractometer Managed by Leigh Loots Cu Kα source X'Celerator detector - has high sensitivity, a large scan range with exceptional performance at low angles, and data collection up to 100 times faster than point detectors. Fixed anti-scatter slits on incident and diffracted beams and Nickel filter and parallel plate collimator on diffracted beam (to allow parallel beam work) Anton Paar TTK450 (with automated sample height adjustment) for non-ambient measurements from -193 °C to 450 °C in vacuum to -120 °C to 300 °C in inert gas atmospheres Oxford Cryosystems Cryostream 700 Plus Compact cryostat (temperature range 80 - 500 K). Capillary Spinner Reflection Transmission spinner with a 15-position sample changer. A wide range of sample holders are available, including porous ceramic holders and zero-background sample holders PDF-4 database supplied by the ICDD (International Centre for Diffraction Data), containing over 180 000 reference diffraction patterns.

Bruker D2 PHASER benchtop powder diffractometer Managed by Leigh Loots Cu Kα Scintillation counter.

Almax easyLab diamond anvil cells and related infrastructure Managed by Leigh Loots and Samantha le Roux Bragg Mini DAC Bragg-LT(G) Plus Be-Cu gas membrane-driven DAC Optiprexx photoluminescence system Boehler microDriller
GAS AND VAPOUR SORPTION ANALYSIS
Micromeritics ASAP-2020 volumetric sorption analyser Managed by Banele Motloung, Rolivhuwa Mahwasane and Marike du Plessis We mostly use this instrument for measuring vapor sorption isotherms under equilibrium conditions. It operates in the pressure range 0 to 1000 Torr.

Hiden Isochema IGA-001 gravimetric sorption analyser Managed by Banele Motloung, Rolivhuwa Mahwasane and Alexios Vicatos Enhanced pressure option (0 - 20 bar) and equipped with a recirculating water bath for moderate temperatures (-15 to 100 °C) and a cryofurnace for more extreme temperatures (-150°C to 500 °C).

Hiden Isochema IGA-002 gravimetric sorption analyser Managed by Banele Motloung, Rolivhuwa Mahwasane and Alexios Vicatos Enhanced pressure option (0 - 20 bar) and equipped with a recirculating water bath for moderate temperatures (-15 to 100 °C).

HyEnergy PCTPro-E&E volumetric gas sorption analyser Managed by Rolivhuwa Mahwasane and Aluwani Kutama Supplied by Setaram Instrumentation - the instrument operates in the pressure range 0 to 200 bar. It is equipped with a standard sample chamber, a microdoser for very small samples (10 to 500 mg), a turbomolecular pump for sample conditioning, an RGA-Pro evolved gas analyser (200 amu quadrupole mass spectrometer) and a CryoPro-2000 temperature controller for measurements in the range -269 to +100°C. The instrument can also be coupled to our Setaram µDSC7 microcalorimeter.

Gravimetric vapor sorption analyser Managed byRolivhuwa Mahwasane and Alexios Vicatos Used to determine the kinetics of vapour sorption This instrument was constructed in-house by Len Barbour and Vincent Smith. It utilises a PTFE coated standard microbalance kit purchased from CI Precision. The high-precision balance has a maximum load capacity of 5 g with a sensitivity of 0.1 μg. The sample is suspended in a jacketed glass vessel that can be evacuated and the temperture is controlled using a Grant refrigerated thermostatic bath. The frame of the balance rests on a half-ton vibration-damped granite block for stability. The software for monitoring the balance and the pressure sensor was developed by Len Barbour. See the CI Precision web site for more information on our system.
THERMAL ANALYSIS
TA Instruments TGA500 thermogravimetric analyser Managed by Leigh Loots

TA Instruments Q200 differential scanning calorimeter Managed by Leigh Loots Equipped with an RCS90 refrigerated cooling system (-90 to 550 °C).

TA Instruments Q100 differential scanning calorimeter Managed by Leigh Loots Equipped with liquid nitrogen cooling (-196 to 550 °C)

TA Instruments Q20 differential scanning calorimeter Managed by Leigh Loots and Alan Eaby

Setaram µDSC7 EVO microcalorimeter Managed by Gundo Mathada, Aluwani Kutama and Alexios Vicatos This instrument operates in the temperature range -45 to 120°C. It is equipped with closed-batch, batch mixing, calibration and high-pressure cells. The high pressure cell can be used in the pressure range 0 to 200 bar. THis instrument can be used to study phase transformations under pressure. It can also be coupled to the HyEnergy PCTPro sorption analyser to measure the heat flow due to sample dosing.
HOT STAGES
Linkam DSC600 hot stage Managed by Leena Patel and Alexios Vicatos This instrument combines an optical hotstage with a single-cell DSC. The sample is monitored using a monocular Meiji zoom microscope equipped with a digital firewire camera. Using a LNP95 controller, the system is capable of operating at temperatures from -196 to 600 °C. Heating can be carried out at rates of up to 100 °C/min.

Linkam THMS600-PS hot stage Managed by Leena Patel and Alexios Vicatos This hotstage can be used to investigate the effects of gas pressure on a sample during heating and cooling experiments. The sample chamber can be pressurised from vacuum to 14 bar. The sample is monitored using a monocular Meiji zoom microscope equipped with an analog camera. Using a LNP95 controller, the system is capable of operating at temperatures from -196 to 600 °C. Heating can be carried out at rates of up to 100 °C/min.

MICROSCOPES
Leica M165 high performance stereo zoom microscope Managed by Leena Patel and Alexios Vicatos motorised focus drive handwheel for motor focus control 150W cold light sources (LED's top and incandescent bottom) cross polarizers Leica DFC290 HD digital camera Image recording software with montage (focus stacking) capability.

Olympus SZ61 stereo zoom microscope Managed by Leigh Loots Used to mount crystals for single-crystal diffraction analysis Equipped with a fibre-optic dual gooseneck overhead illuminator, a halogen transilluminator, cross polarizers and a rotating stage.

Olympus SZ40 stereo zoom microscope Managed by Leigh Loots Used to mount crystals for single-crystal diffraction analysis Equipped with a fibre-optic dual gooseneck overhead illuminator, a halogen transilluminator, cross polarizers and a rotating stage.
MISCELLANEOUS
Bruker EMXmicro Electron Paramagnetic Resonance spectrometer Managed by Delia Haynes and Samantha Strydom

Buchi Glass Ovens Managed by Banele Motloung and Gundo Mathada We have four of these ovens for heating samples from room temperature to 300 °C under vacuum. These ovens are generally used to condition/activate samples, or to grow crystals by sublimation.

Tousimis Samdri-PVT-3D Supercritical CO₂ drier Managed by Banele Motloung We use it to condition samples.

Analytik-Jena SPECORD 200 PLUS UV-Vis spectrophotometer Managed by Leena Patel Dual beam instrument equipped with a diffuse reflectance accessory (integrating sphere). Wavelength range 190 to 1100 nm Spectral resolution 0.5, 1, 2, 4 nm.

Bruker Alpha P FT-IR Spectrometer with ATR attachment Managed by Leena Patel

FTS1000 Ball Mill Managed by Leigh Loots

Pfeiffer Hi-Cube turbo pump Managed by Banele Motloung Used for activating porous samples

Cryomech LNP60 liquid nitrogen generator Managed by Leigh Loots Production Rate = 60 liters per day 210 liters (56 gal) Dewar Air cooled The liquid nitrogen from this system is piped into a manifold in the diffraction laboratory.The cryostats of the three single-crystal diffractometers are fitted with autorefill devices attached to the LN2 mainfold.

Gas cell manifolds Managed by Banele Motloung and Gundo Mathada

Varian 3900 gas chromatograph Managed by Marike du Plessis
Management of other facilities: Synthetic lab: Raymond van Rijn and Banele Motloung All vacuum pumps: Leena Patel